Full text of "Popular Computing Weekly (1983-09-22)"

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35p 22-28 September 1983 Vol 2 No 38 



WEEKLYi 



Spectrum software 

of Ihe liJlesl g^imts for Ihi; 
Specirum induding Manic 
Miner and Jumpini; Jack. 
See page 16. 

Logan's Run 

David Kelly talks lo Ian 
l.ti|an about ZH(1 macliitie 
code and the ZX 
Microdrive or page 15. 

Rings of Saturn 

Maurice Gavin presents a 
simulation program of 
Saturn and its rings on 16K 
Specirum. See page 20. 

New releases 

All Ihe latest soliware 
games including Dcvi/s of 
Ihe Deep from Richard 
Shepherd and Beta Basic 
from Betasoft. Sec page 46, 

I^STAR- 

I Conned 4 on 
I Commodore 64. 
I See page 10. 

Lgame^ 



News Desk 



An enterprising 
move from Elan 









Called the Enterprise 64 and 
8 — the two models differ 
\y in Ram capacity — both 
II be in the shops in April 
S4. Prices svill be £199.95 
d H299,95 for ihc two mod- 



The Enterprise 
based with .12K t 
and either (AK or I 
Rum and Ram an 



, Z80A- 



resolulion display in up to 256 
colours. S-ociave four- voice 
stereo sound, built-in word- 
prncessing software and a 
built-in joystick for cursor con- 
trol and games. 

The Elan Enterprise has a 
complex system of 16 display 
modes which can be mixed 
on-screen. Explained Roben 
Madge, Elan's technical direc- 



■■1 \ 






by the speed of the machi 
plotting." Text modes rnnge 
from 42 x 28 characters to 84 
Continued on paga 5 




Oric will 
compete wHt 
IBM Peanut 



standard and v 
there with it." said One's mi 
aging ditectoi Barry Munc 
ter. "Oric will produce a pro- 
duct which the Peanut will be 
compiitible with." he added. 



a 8(l86-ba.'»!d 
It," said Tom 



Gboul that the Peanut wil 

be c.mp.ntihiL- with Ihe mufi- 

Continued on page S 




SHADOW FOR THE BBC 32K 

ChireB Mlciro Supplin 
DWI nw, IIS InrrtlW FUH, iGhih. OnNn 



Continued on page 40 



BRITAIN'S HOME COMPUTER WEEKLY 



DRMUIN 




This complete collection ot books explains 
everything you need to know to get the rrast cut 
Dragon 32. The most exciting games, the latest 
prDgramniing techniques and the most practical 
step-by-step instructions ~ everything necessary to 
make your Dragon roar. 



Enter The Draton 

|ni<Oia|on3;inUac 




NewB Editor 

David Kelly lOl-73'l 2664] 

Software Editor 

Grahafn Taylor |01 -734 2953| 

Production Editor 

ie Con si able 
Editorial Secretary 
Sarah Owen 

Adverllsemenl Manager 
David Lahe|01-734 0840] 

Advenisemeni Executive 

lirMacinlosn 101 -734 3443! 
Classified Executive 

le Davis |al -734 36881 
Administration 
Theresa Lacy)01-734 3454| 

Managing Editor 
Duncan Scoi 



Popular Compuling Weekly. 
12-13 Lillle Newport Streel, 

)r WC2R 3LD 
Telephone, 01-73H106) 
Published by Sunanine Publicalions ltd. 
Typeseliing, orlglnal>on and printing by 
Chesfiarti Press, Che sham, Bucks 
DiBlnbLlBd by S M Dislnbution 
iondonSWg 01-274 8611 . Telex. S61M3 



ABC 



1 nol be more lliaii 3,000 words long Ttie 
15. and any accompanying programs. 
Hhouia Be onginal it ib oresking Ihs WW ol 



Popular Compuling Weekly cs 
publish, although we will alwa' 

H-28 SEPTEMBER 1983 



i This Week 1 


News 


5 


Elan home comoulers 
Letters 


7 


Pnnltoplol 

Star Game 


10 


Connect 4 on Commodore 64 
Street Life 


15 



Reviews 


16 


John Scriven looks a( Spectrum 




Programming 


18 


Vic20 gameswriting — part VI 




Spectrum 


20 


Hings Ol Saturn 




BBC In education 


24 


Compuier graphics 




Commodore 64 


27 


Hi-res graphics 




Dragon 


29 


Appronimating t unctions 




Open Forum 


30 


Five pages o( your programs 




Adventure 


37 


Tony Bridge's corner 




New releases 


45 


Latest soltware programs 




Competitions 


47 



Puzzle, Top 10. ZIggural 



Sinclair's tiai-Screen tv may, or may 
:, do for television what the transis- 
radio did (or wireless. II will certain- 
ly do a lot (or Sir Cllve's reputation as 
Britain's 'golden boy' ot electronics. 

The (lai-screen tv is nol a new idea 
— scientists have long been speculat- 
ing about tv screens just a Vsin thick 
which could be hung on walls. Pocket- 
sized (lai-screen Ivs have also been 
mooted for some time. But, until thi 
year, no one had really been able to 
produce a commercially viable flat- 
screen tv tor general consumption, 

Sony pipped Sinclair to the post with 
its Watchman (lat-screen tv, due in 
part to industrial trouble at Timex's 
plant in Dundee. But the Watchman, 
brainchild of Sony designer Yasuo 
Kuroki, IS bulkier and more expensive 
than Sinclair's offering. Even the ' 
proved Watchman II will cost about 
$200 in the US, compared to Sinclair's 
C79.95 in the UK. 

Sinclair's flat-screen tv may nol be 
the first, but it is the cheapest, it is also 
one ot the most technically advanced, 
being able to receive signals in bolh 
the UK. US and Europe. 

Once the pn^lems ot producing s 
colour tlal-screen tv ate solved, Bri- 
tain's micro users will be able Ic 
dream of a new generation ol compu- 
ters that will be truly portable 



arcade game and the object it 
all the bugs whicti attack yoi 



Subscribe to 
Popular Computing Weel<ly 



A new generation of 

Computer Gomes... 





w One's planned compulirr 

tested market — straddling 
■ gap between home and 

« market will prove Ui be by 



I. The CI 



y plan 



iin December, 
.id Barry Muncaslcr: 
(ealisiically there won't be 
any in Ihc UK before Chrlst- 
as. We now have i! ull work- 
g — It just depends on ihe 
lanlities oS ifrlves which 
iiathi can supply. 



Flat-screen unmasked by Sir Clive 



SlRCIiveSmdaitiinvL-iledhis 
flut-screen tv in London las! 
week. Slighfly larger than a 
cigarette packet, ihc black and 
while tv is the result of a 
;ar development ptog- 



The 






off a lilhiiim 

Polaroid, though It can also 
run off the mains with the 



the tv to work in tht US and 

Europe as well as in Ihe UK. 

Priced at liTy.y.i. including 

is considerably cheaper than 
Sony's Watchman tv launched 

Sinclair regards his flat- 



MllTOI 

be disappointed to learn ihal it 
is nul really feasible to link a 
micro with the new iv. The 2in 
screen is simply loo small for 
program lines lo be legible. 



Revision what the tronics giant. Maisus 

transistor radio did for wire- announced the deve 

less.'' of a portable colour ti 

Sir Clive is currently work- Set. 




ZXSland 
Spectnim 
taken to task 



£28.7S. A Spectrum 
cartridge module isals 
way. in a couple of w 
£63.56. 



people up a bit," says com- 
pany founder David Husband, 
"In the com pule t" niarket the 
hardware has jumped forward 
■ while the software has stayed 
still. 



(asking system with a ZHO and 
16K." 
The 2K ZXBl Rom features 



I limes, Machine- 



first unit. The first of these 
peripheral units is sche- 
duled for June I9K4. two 
m (h ft I h S ft*are 




The ZXKl Rom rc| 
nent can be undertaken I 
jser hut il involves removing 
Jie existing Basic Rom whi 
s soldered in. ZXSlscomph 
*ilh the Forth Rom in pli 

Den sham Com- 
Ashley Road. 

D Ihcr the ZXSI 

ru ulti-tasking sys- 

m m D Id Husband. 2 

G R d. Branksome. 



Barbican 
goes personai 




1 Benson Street, Cambridge CB4 3QJ 
Telephone 0223 322905 



COMPUTING WEEKLY 



LETTERS 

MarUan 
error 

Before we lav the Marlians 
lo resl (my leccer. PCW. 
1-31 Augusl) would you 

at the Mnnian word for 'yes" 
is qwl not go'l. OthervJise my 
remarb do not make sense. 



Apologies. I am afraid tlial our 
knoHkdge of Maiilun is suEh 
th« qKlllnK error slipped 
Ihrough unnoticed. 

Speedy 
reviews 

Tjaving ju5i been inlro- 

v/s. Ho« do vou do it.' The 
iew5 are always inieresing, 
jting your Microdrive re- 
vt as an example, 
always turn firsUy to your 



c located m the tonnet- 
ite up with, allowing only 



cannot get the Delta lead on 

cable made up. Another point 
is thai Dragon Data appears to 
have no intention of selling the 
controller separately. 
Come on. Dragon, play fair 



:ces,sary expense. 

Duve Barivll 
riViW So/ware 
8 Azalea Close 



Play fair, 
Dragon 



by 1 

What Dragon I 



in fact 



Cync 



well, Salop's letter 
dhke to inform hiir 
score for Or 
651.«1U. The completi 

look jusi over two nours 

Paul Holden 

1 10 Crescent Road 

Great Lever 

Bolton BU 2JR 



Random 
statement 

Tf any Dragon owners arc 
lupsct with the apparsnl lack 



generated from thesam 
ing point, resulting in th 
of Miistermind oi 



The long wait for the arrival 
of Dragon Data's discs is 
-.r. However, the speed in 
ich the Premier Delta sys- 
1 came onto the market 
St have taken a large share 
of the dedicated Dragon user's, 
who now might want to run 
Dragon based disc software on 
Iready bought ^in high 
Cannon drive. 

isthol, at first glance. 
Dragon Data has built a type 
in'Compatibility into its 
system — the one half height 
drive (with a location for the 
second) is a standard drive and 
1 be run with ihe Delta 
eonliollei. but only allows vou 
no byles, not Ihe 185 allowed 



al programs, in future issues — 
preferably al the expense of 
the ceaseless round of Zap- 
Ihe- Alien drivel (may [ also, 
en passant, add my vote to the 
requests for a Spectrum 
machine code series). 

However, Mr Choy's prog- 
ram, as printed, contains a few 
bugs which prevent it, for en- 
ample . from salving: 

Also, while it will tackle: 



successfully, the related equ: 



Debugglns 
exercise 



The program from T Chnv, 
The Root of Ihe Prohlcm 
(PCW. R-M Scplemberl was 



follow 

(a) Omil line 538 entirely. 
lis only purpose is lo prevent 
you demeaning the dignity of 
your machine bj^ giving it tri- 
vial cubics lo solve- The snag is 
thai Ihe cubic routine, as well 
as solving cubics in its own 
righl, also gets called by Ihe 
quarllc routine; and a perfect- 
ly genuine request lo solve a 



<b) Line 620. as prinK 
will fail if R is negative, sit 
Ihe Spectrum uses logs to 
this calculation. Change il 



(d) (The big one) Line 850 
includes Lei V = Sqr P2. The 
snag is that the machine will 
always take the positive square 
root, while sometimes the neg- 
ative root is required (this is 
why equation (2) fouls up), To 
debug, change line 857 tc 

857 DIMAia,Z|:IFZ.U.V< 






e of 



Al! in all. an excellent de- 
bugging exercise: I thoroughly 
enjoyed myself. However," 
something in my water lells me 

mind when you published il, 
Jim Hind 
5 Park Sir 
Southend 



Plot to prkrt solutions 

With regard lo the query in 
PCW 25-31 August, in 
your Peek and Poke feature, 
relating to conversion of P/or 
to Pnni, I offer the following 
solutions. I'm not certain what 
your correspondent had in 
mind, but I hope these ate of 



ie help. 



;nf n 






;nce can be generated bv using 
he same "seed" value for A. 
For an unrepeatable sequ- 



With 




to the Sereeili 






fact returns a 






value as stated 






Micftae) Kirkland 




1 








Rainhil, 






Presroi 




Men 


eyiideLiiSLT 



?rint to I'lot 

lo REH GO SUE after any PRINT 
statenant. On exily Pi-OT 

= 0£ition is at the botto» nsht 
^f last PRINT Pixel- and is in 
variables x and u • 

3,000 POKE S3e7"7, 7-PEeK a363S»S ^ 
iBlB POKE a3e7S, (PECK 23689-3.' *e 

a,ese let x=peek sse?? 

iS3e LET y=PEEK SSc/B 
lO+C PLOT X - y 
1O50 RETURN 

Plot to T^int 



ISOa PDKE 23638, PEEK £3677^6 
aBifit poke a36S9,Sl-PEEK 3367S,.-i 

aaae let i<=.pffEK sseas 

2S30 LET yxPEEK S3B86 
IB^ei RETURN 



22-28 SEPTEMBER 19B3 




RICHARD SHEPHERD SOFTWARE 

USE. 21 25 ELMSHOTT LANE. CIPPEPJHAM, SLOUGH, BERKS TtL {06J86| 6353 



„, ,._ i-i-'o Ljtronr available now 

YEP FOLKS — ITS HERE 

Dragon 
Com. ()4 

CALirOUNIA 

mm&m mwmm Mq 

HOWDE DO PARDNERS '"'^r 

This here's Prospector Jake, I sure am havin' one :/Tf\ 

helluva time tryin' to peg ma claim vi/ith those damned ~i L 

Injuns a hootin' an a hollerin' all over this territory. Ma job tl | 
gets harder as I move from one Gold Field to another. I ^.j;%. 

know that is me an' ma stubborn hornery ol' Mule here 
know of 24 rich an' I mean rich seams of pure Gold. All it needs to make 
this here ol' critter happy is that you help me peg every doggone last 
one of them claims. 

Can YOU help Jake become rich, help him peg his claim, dodge the 
arrows avoid the tomahawks, and plant the Dynamite in just the right 
place?. . .YOU CAN!!! 

YIPPEE Git yer Picks an' Shovels and join the CALIFORNIA 
GOLD RUSH . . . NOW 

Amazing Arcade Action . . . Stunning Sound and Graphics 
Available NOW for Commodore 64, Spectrum 48, and Dragon 

^ #aS® including P&P 
SPECIAL OFFER SPECIAL OFFER SPECIAL OFFER 

Order CALIFORNIA GOLD RUSH before August 14 {TR F E 
and get a 1 0-game Cassette of terrific games ... « « i^ i^ 

COMING SOON 

LEAPIN' LANCELOT; Medieval Machine Magic to enthral you 
GALACTIC SURVIVAL PAK; Every Astro-Traveller must have this!^ 



tjn:? 



UK WICROSVSTEME 

BELLINCE NORTH fiMPTON 



22-28 SEPTEMBEFI19e3 



Connect Four 

A new game for the Commodore 64 by Les Allan 



j^onnact Four tor Ihe Commodora 64 
O utilises hl-resoluDon graphics to pro- 


V 


a.scpci 


mlhori^onwll 






nMlB, 


luce an on scraen version of tne popular 






ward game of the same name. In order to 
















made up o1 4x3 characters and the 








graphics lor the row nuijibers are arranged 








o be In me centre of each disc Simons 




ilUaT 




3aslc commands have been used 








(iroughoul. but lHe program can be easily 














nlH and procedures 


Dunrig play, the seieded row for each 


the program lis 


ing should provide 


disc IS made By pressing keys f lo 7. 


underslanding 




'ressing Fl resets a game, whereas F7 


bul jus 






■ecalls Lhe Inslruclron page prior lo the 


listing: 






start of each new game. 


Notes 






Variables used are as follows: 




earscrs. 


nicainiibiacH 




POPULAR COWPUTII^G WEEKLY 



















166 IFK»-"5"THENCS-52330:T-24 
168 IFK(-"6"THENCS-52336!Y-30 






IHHHHi 


^^^^^^^^g 














170 IFK(-"7"THENCS-52342:Y.36 












172 rFPEEI«CS)03eTHENCm.L KEVB 












OflRD 








■■■■■■■■H 


IbMHHUbh 




174 EXEC PLHV 

176 ■- 

178 REM «*K« DROP DISC ***« 

lea : 








Discs nay be co 
•ither horizonr 


nnscted together 










ar Obliquely to 


plac'e 4 in a row. 
















182 REPERT 








Use fcetf-t 1-7 to 
[FIJ ........ 


select !/our row 




184 IFX>0THENPRINTflT(V,X-l)V»; 
186 PRINTflTtV.XJZtXl; 
IBS X-X*l:CB-CS+40 
190 FORT-ITOZS^NEXT 








tF7J petal 


3 instructions 
















192 UNTIL PEEK<CS*40>O32 

194 IFZ*-CHR»<J30)TH£NZ*-CHR«<3 














10 ! 




0):EL3E-Zf>CHR*(l50>' 




IZ REM WWt CLEW SCKEN/CaOK 


82 PRINTflT(34.20)".'!IBVn«LESnl 


196 EOKE198,0:X-0;C*L1. KEYBOARD 




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IBLLflN'S^EXEC OELBV 


198 ' 




14 : 


S4 FORV=iTO10:EXEC DELHV 


200 : 




IS PRIHTCH»»(I47)-COLOUfW.0 


ge NEXT 


282 PROC PELBV 






18 OPTION10:PBOE22 


88 IFTI*C"0Ca0ia"THENPRrNTCHft» 








» DL-iB:Ti*-"eB00ee" 


(J47>:CflLL PRINT TITLE 


206 F0RT-lT075.f«XT 






22 EXEC MUSIC 


90 IFTI*>"0W8Sa"THENCnLL GflME 


208 END PROC 






2< : 


START 


210 ■ 






ZS fiEM «««• TITLE CMWflCTERS 


92 ■ 


212 ■ 






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214 PROC HI-RES DflTR 






28 : 


96 PROC INSTfiUCTIONS 


216 ■ 






se €*-"»■ JOMii ni ai ni ni 


98 : 


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100 PRINTCHRftH?) 


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102 HIRE86.7!COL0UR7,7 


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36 PROC PRINT TITLE 


130 ■ 


266 9BBBBBBBP 






38 : 


132 PROC OflME STflfiT 


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136 PRINTCHR*C147).COLOUR0.e 


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62 PRINTflT(S.3)CKR»(28)0*.EX£C 


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150 GETKJ 


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152 tFK*-CHR$(133)ANDCS"0THENP 


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80 PftINTST(27,14)CHR»<194)M,EX 


164 IFK*-"4"THENCS-523Z4;Y-18 








2-28SEPTEM 


ER 1933 






'^ 



9 MINEFIELDS 
ARMED PATROLS 
ENEMY BASES 
STUNNING SOUND 



WIRE-GUIDED MISSILES 
HELICOPTER GUNSHIPS 
PERCUSSION GRENADES 
NIGHT ACTION FEATURE 



MINE-BLOWING HI-RES ACTION FOR THE DRAG0N^2 



LIONHEART £5.45 



RT £5.45 - Unique. l»o-psn romp Arcade- ^T^'^T'l^T'^l F 1 I V 1 
,. yo.; ».d >n lU H.I, L,.d lo m<,.« „., ^^^^^MitJi^^UmA 



Crusade against ine Sullan Saladin. Dragi 
DEATH'S HEAD HOLE E5,45 — ' 
slory lo The Sun The eyes of tne 




POPULAR COMPUTING W 



3ie llE$l6n^.■K^0^*l^^*8 

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362 8 

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28SEPTEMBER19a3 



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588 rEsroK2.*eee0+!4')«e 



S22 a 

524 BBBBBBBBB 

526 DESIGN2.*Ee08+145*8 

328 eBBBBBBEB 

530 9BBBBBBFB 

53£ aBBBBBBB, 

534 9BBBBB..B 

536 9GGBBB... 

538 eBBBBBFBB 

540 aBBBBBBBB 

542 9BBBBBBBB 



544 BES: 
546 9B. 
548 a.. 
558 a.. 
552 as, 

S54 «., 
536 9B. 
5Se 9B. 



■GN2,tE0e9+146*e 



562 DESIGN!. *E000+147*B 



570 

372 9BBBBBBBB 

574 9BBBBB..B 

576 aBBIBBB.. 

578 aBBBBBBBB 

580 DESICN2.«E0a0+14e*e 

582 a. ..BBBBB 

384 aBBBBBBBB 

586 8.. 




610 aBBBBB..B 

612 9EBBBBB. . 

614 aBSIEGBBB 

616 BESION?.tE00e+150*8 

618 a. .EBBBBB 

620 aB.. BBBBB 

622 aBBBBBBBB 

6;4 a. .EBBBBB 

626 SB.. BBBBB 

62S SB.. BBBBB 

£30 9..BBBBBB 

634 IIESION2,tE800+151»9 
636 aBBBBB... 

635 9BBBBB..B 
640 9BBBBBBBB 
642 9GGBBBBB. 
£44 aBBSBBBS. 
£46 9BBBBBBB. 
£48 9BG5BSBB. 
550 9BBBBBBBB 
652 BESIQN2.;- 
654 a. ..BBBBd 
656 9B,.BGGBG 
638 a.. EBBBBB 
££0 9.BBBBBBB 



670 END PROC 



676 PffOC MUSIC 

678 : 

688 yOLlS 

682 URVEI , 80810000 

£84 ENVELOPEl, 8.8,8.0 

666 M1«-":512K5K5B'M" 

688 fl2t"''0; 

nSESESC 

690 mt-n2t*'E5KamstFZiris.sr 

S«35t5B:5m5B:5tt5C!IE!»!i" 

692 ri3*""C3IC5rr" 

694 MUSICS. Ml «+ri2**ri2«+M3* 

696 PLflve 

696 EKD PROC 

700 ■ 

702 : 

704 PROC PLfiV 

TO6 : 

708 V0L3 

710 UHUEI. 00018008 

712 ENVELCPEl.e.e,8.0 

714 P»-''aiZi:5K5»=3«^5EC5« 

5«J!KJS" 

716 msice.Pt 

718 PLfiV2 
720 END PROC 

722 ■■ 
724 • 

726 REM #ft#M<l)lfl»llt*#f*tt))***l')**MI 
728 REM )HH)#)m(|##|Kt««»«tHlf(HI*»» 
730 REM Itlttt #«*« 

732 R01 »»## CONNECT FOUC Htm* 
734 REM »»»# COMMODORE 64 *«** 
736 REM tUtW **** 

738 REM *»»» SIMOH'S BASIC «*»» 



742 REM tUHHt LES flLLRN »#»« 
744 REM (HUlIt 2STH AUG 1333 •••« 
746 REM t 
746 REM # 



r KAV NAME 13 -, 

PIAMONR PAN PIAMONP 
I'M A PRJVATE COP. I 
WORK THE BIG APPLE _ 
A 5EETH 1 IMG METPOFOLIsI 
' Fl LLED WITH HU^^AM " 
Ml SERy AMP CHINESE. 
TAKEAWAYS. 



NORMALLY I 
ONLY PO ROUTINE^ 
PIVORCE CASES BuT\ 
WHEN SHEWALKEPI 
INTO AAV OFFICE 1 

FOUNP MYSELF 
ItMOLVED IN A CASE 
SO STRANGETHAT^' 

IT MADE THE 
BIG SLEEP 

ljdok like a 

CAT NAR., 



VElis 



-ipait in 






iVM„.. "' 












*c„„.'*«8lin.?*!'M 













v-'^r^r*"* 



VranWW 



s liioih. 



but thi> 



ni»".."S, for '"""« ,i't. ' 



\ piling':'-* j'' 






street Life Street Life Street Life Street Life Street Life Street Life 



Logan^s run . . . 

David Kelly talks to Ian Logan, author and machine code expert 

Uaulhoiily on zao machine-code, Ian Milchell who wrote rne WDOtw." 

Logan stni regards himselt as an aoialeur lan's firsl book lor Melbourne House 

enlhiusiast was published in September 19Bi — 

A graduate in medicine from Shefdeld, almost exactly a year after his tirsl. 

he dJalilied as a GP Bui, his lirsl attempi Neil came a chance meeting wilh Frank 

to get involved with compulers was. a O'Hara — a government slatislician 

failure — he was turned down for a job as "Frank thinks and lives numbers," says 

a doctor lor ICL "They gave me a nice Ian, "And he understands all the 

lunch, but I didn't gel the lob " maihemalics which i don't." Together Ihey 

After thai, he spent nine years working wrote Undotslanding Your ZXB1 Rom. "I 

as a GP — stiii wilh a taint hope of slarled ZX81 disassembly from Ihe front, 

somehow, someday, becoming involved in and he started from the back We met in 

computers. 'he middle 

In 1930, lie joined Ihe Lincolnshire Then the Spectnjm came out — Ian and 

lilicro processor Society, Through the Frank have recently written Thg Complete 

group he met people who had Pels and Spectrum Rom Disassembly lor it "The 

Tandys. "I borrowed a Pel for a forinighl book is doing very weli — because nobody 

— and It sat on the lable downstairs. I else has attempted anything like il," 

didtiT really know what lo do with it." ftir the last couple ol months Ian has 

Then he bought a ZX80, "Bob Maunder been preparing yet another book: The 



he magazines, saying he wanted ZXBO departure for tan - 

jrograms,' says Ian. "I pfioned him up willing aboul his o\ 

ind discovered i knew more about the From Christmas 

nachinethan he did " two days a wee 

The two decided to produce a book lor software lor the 

he machine — which became lans first necessary* 

look. A small spiral-bound handbook 
ed The ZX80 Companion. 



for the firsl lir 



Speclrui 



d Ql it 






Bob and another writer, Terry Trotter. I 
came out in September 1980, 
Ali ol Ian s knowledge ol Ihe ZXaO is 

seif-taught. Back in 1980 Ihere were no 



experts ' 






lans ne>l book, on ZX80 ma 
and suggested he try to fi 
puBlishet, "There I was, a we 
ZXB1 was launched, going 

publish a manuscript wnllen for Ihe ZX80, 
"Aller a couple ol people turned me 

Mei bourne House. 

"I gol a phone cali from Austraiia when I 
was over at the village hall mowing Ihe 
lawn and my wile came rjnning across to 
lell me. The call was from Fred Milgrom 
and thai is how I started writing lor 
Mel Bourns House." 

Fred li^iigrom asked ian lo convert his 
book lor the ZX81 : ■'Meibourne House 
apparently made a lot of money oul of 
some sensational book published in Au- 
stralia aboul lemale sen hormones But 



)k on the Microdrive and Interlact 
■ published in eilher late Seplem- 
ber or early October. 

Since working on, and wnling a book 
aboul, the Microdrive, Ian has became 
[ something of an authorily on the device 
"People don't seem to be as ancilsd aboul 
the nelworking possibililies as I thought 
they would be — there is no reason why 
you cannoi join up Spectrum Net to other 
computers. Networking is great lun. 

"The other thing people don't seem to 
have realised Is that you can pass any- 
thing on the RS232 and siore it on Micro- 
' drive — 11 you are prepared lo use Ihe 



IS some very good program 




B them direct. Although not 
difficult technically, it might be dilflcull lo 
manufacture it al a tow enough price — Ihe 
Microdrive has a big ULA in it, doing a lol 



software hooks' to enable users lo access 
nDUIines in the Interface fiom This means 
that anyone can now add new commands 
to the Spectrum. "You can add what you 
like — add new languages if you want," 
These can only be wniten in Ram but, il 
stored on Microdnve. Ihey could be loaded 
in each time belore using Ihe machine. 

When Ian was wori(ing at Sinclair, he 
mel Scott McCoun. Scott was in 
charge of writing the system software tor 
the Timex 2000 machine, the US Spec- 
trum equivalent. He asked Ian to help — to 
go over lo Ihe US and write software for 



the Spectrum," says Ian. "The machine 
. was a 1981 design and requirements tor a 
19B3 compuler have evolved since then. 
They were going to have to redo the 
Spectrum printed -circuit boanJ lor the 
TS2000 to satisly the US FCC regulalions, 
and lo make it compatible with the NTSC 
tv standard. So, while they were about it, 
they decided lo produce an enhanced 






"I'm not sure il Timen made tl 
decision — maybe they should hi 
put out Ihe Spectrum, more or less 
and gol it oui over there earlier. " 

During his two weeks stay with 



syntax checking and 
small bugs in the Specinjm's own Rom. "I 
wouldn't want to make loo much of the 
Spectrum's fauils. It is a very successful 
machine, ' he says. "After all, it is not often 
you need id use Ihe number — /n(6S53e." 
After the Microdrive book comes prob- 
ably a TSSOOO version ol lan's best-selling 
Complete Spectrum Rom Disassembly. 
again with Frank O'Hara. "I don't know 



irt of dr 



ling fri 



Ihing Ic 



le plan was 
t I got so 
le software 



Vic20 all 

frustrated at the 
was organised . 

"Perhaps t ought to sit down and wrile 
some programs — but I don't like writing 
games very much, I am going to have lo 
learn a bil about 16-brt machine language. 
That's going to be all the rage next year, 

'What I have lound is that I like problem 
solving I enjoyed my work with Sinclair 
and Timex — and I'd like to do more. I'd 
like to continue to be involved with the 
compuler industry and I dont feel as 
though I am at present. People like ma 
don't gel employed by a company if they 



22-28 SEPTEMBER IE 



REVIEWS 

Hitchcockian nightmare 

John Scriven picks his way through another selection of 
Spectrum software 

In Ihe morlhs since Ihe Spectrum firal Ifie dlfflculiy level. The game is sel off II 

nosed its way on lo (he rrarkel, Ihere has coasl. with a view from the seabed to tt 

bean a drastic improvement in the avail- sufface. You are provided with a base Ih 

able software. can be moved left and right across II 

The tirst games were mainly coloureO sand, liring al sharks IhaL swim betwei 



pick It up, open it, decode it, or in taci, do 
anything — you simply retrace your loot- 
steps and leave Ihe building. There are no 
I the only thing you 



guards 10 stop you ai 
play against is the cl 
challenge in this game. 



Yel a 



■r progr; 



n that a 



s Schizoids 



poison pellets or 

The idea Itsel 

resulted in an interesting game. However. 

Ihe sharks only swim lett and right and you 

control how close to the surface 



copies of 2XB1 

slow Basic programs thrown in lor good 

measure. When programmers had got the 

hang of smoolh movement in machine 

code, Ihe standard began to improve. 

Even without the definition ol Ihe BBC and 

the sprite facilities of Ihe Commodore 64, 

there is prodatjiy now a larger selection ol they swim. Once you've destroyed 

good Specinjm software on the market layer, another appears Perhaps 

Uian for any other machine. 

Having spent several months with other 
machines, it was a pleasant surprise to Pa 
presented with 3 pile ot games software lor 
the Spectrum that was generally of a good 
standard Although the old favourites were fli 
there and some novel bul ollimately Ijormg ir 
games, there was some ol the best TV (! 
enterlainmenl since Anne Diamond first tr 
graced my early morning screen. d 

from Artie includes Ihe copy- 



a great deal al 
from Imagine. The casselle blurt] invit 
you to be a space dustman and to tii 
shove all the galaxy's garbage into t 
nearesl black hole with your Space-doz 
The main disappointment is in the display. 






s. Not ai 









right ni 



ibtlety, but Ihe game rapid- 
ly became bonng and yawningly predict- 
able. II you suffer from insomnia this could 
be the ideal program for you. 

FireDirds Irom Soltek produces waves Ol 

flapping cosmic vultures that either crash 

inio vour base or drop unpleasant things 

1 your head It you kill enough of 

mem, while motor-cycle helmets progress 

down the screen and generally gel in the 

_ .. _ . . _ .... , _ way. Apparently, a mother-ship makes an 

« and instructions on the loading appearance at some stage if you can put 



Usually, you end up being s platted by 
some strange-shaped piece of i 

yourself. One wonders which unlortunate 
part of the galaiiy is at the receiving end lor 

have seen something like ii in PCWs 
offices — perhaps that's why they've 
changed their address recenliyl. 
Sentinel from Abacus is original anc 






space 
naped mother ; 



many companies up wi 
seem lo employ nowadays. There are 

options at the start lo choose game dilficul- The & 

ty (1-9), the number of players ^^-2) and I whici 

game variation {I -4) This latter choice can zoom ol 

provide you with mutant invaders and right, yo 

bombs from different angles. Should you pretty lit 



e ol If 



GobblB-a-Ghosi Irom CDS 



n this Iween tndivid' 






It do the same. There are 
i-coloured displays in be- 
ll games and this pack- 
' worth considering if you 









There is even a lorce field thai will lempor- 
ariiy repel invading aliens. Fi 
and using clear, high-resolutio 
for the space -cratl, this game pr 
above the usual slandarel of space games. 
Another game th. 



n graphics 



erfri 
Pacmen in slightly diflerent guises. Gob' 
bla-a-GhosI with four ghosts and lour 
power pills provides i "' 
packaging but nothing 
you. The controls used are ( and Q lor up 
and down, and 9 and O lor left and right, a 



lerable lo Muncher's use 
K for up. Al least manufacturers 
he main to have stopped using 
x)nlroi keys, apparently logical, 

Gobble- a-Ghosi is reasonably dilficult 



beautiful demonstration game at the star 
Unfortunately, although the prograi 
' I with no difficulty, the game itsa 
fl to slarl. so I can't say how good 




^Irom Ellin Software 

promise The title page is good, 

in select Ihe number of players 



jflwilh 



ed, although not in 

ating the maze ol ro 

level one and three n 
There are maps posi' 

storeys. 

an envelope on ihe « 



building are display- 
particularly m gener- 
)ms (20 seconds for 

loned on some of the 
i you to three other 

all YoudohLhaveto 



carelul thought is Spectra 

Romik Software. Although ii 

version of City BomiDer. it cai 

with a variety of joysticks Tbi 



POPULAR COfiflPUTING W 



REVIEWS 



yoj succseO in cteanng \he scraen. you 


the screen, each one containing gaps that 


r^ ^1 




move in both directions. You start al the 


1 


your assistance and lets you lake off to 
aitacd yet anoltier area of Amsterdam |l 


bottom of the screen with eight lives and 
have lo (ump through the gaps lo the next 
level. 
Allhough the holes are essenliai lor 


. < ..... 1 
-1 




.■.t 


know me Dutch are generous, but this is 




ridiculous). 


moving up the screen, they also drop you 






Allhough illogical in concepi and du- 
bious In morality, 11 s fun to play. Also 
Included is a copy of Bmakoul. which is 
Just as boring as 11 was when it first 


back should you Be running in the wrong 
direclion. If you fall lo the boHom you lose 
a life. Each time you reach the top, a fresh 
screen appears, identical except lor the 
addition of a hazard (jumbo-jets, etc] 




-J 


■r 


1 


appaarsd in pubs six or seven years ago 


L J 


— but one shouldn'l complain about a 


Each screen cleared results in an extra 


freebiB game, even if you'll rarely want to 


hazard lo avoid, so the 20Ih screen has 19 


play It, unless youre feeling nostalgic. 
Having looked at a rather weak game 


mo'r?inteSnoTn^blt^^n'sc?ee'^ftw2 ^"'""^ 9«'"« ^fP^^'^ "^ *« ^«'''«- 
linas of a verse aooear '^^""^ Mrnerlrom Bug-Byte has an amus- 

' r„i%"rtK;. ,.™ .nd would 3,"«-» 7 "™ ,»•' »" 'r ,■ 


Irom Imagine, it was a pleasure to find one 
of theirs Ihal has appeared on the market 


more recently called Jumping Jack. This is 
great fun, original In concepi and very 
addictive. 


wno can ace rusi at o a o o as ^ 

c^ashesTrhead aoa nst the cel^no 1 ^"^ ^''° i^-^P- ™^ '^=' '"°^«"'^'" ^^ ™«l 

su^^sithtronttXiip^^rx; rsti'cr'^'a^tu'j'/siro^u^ti^irir"- 

all. Jumping Jack and Vossa Hughes Bolh ^'^n^^^l^^^I^itf JK!V'L''l'°,S,^i'];,'ll- „„ 




f\n the surface a simple gams, al higher 
Wieveis it requires great concentration 


and the ability to keep a straight face while 
being pursued across the screen by a 

shot-gun. There are eight moving lines on 


originate from Liverpool, 

1 have left until lasl what must be the 
most intricately conceived piece of soft- 
ware for the Specirurr) since the first 


jumping from level lo level up the display 
[while negotiating one-way conveyor tislts 
and disintegrating floors) enables him to 
collect several keys positoned in awkward 


Supftltor Progr-m 

Anic Computing (node's 


Price ' ValuBd-IO) 


places. Should you manage lo guide him 
to success before his air supply runs out. 
he has to make his way to the boltom of 


BrarWBBDurton 




the screen again and em through a 


DtHnskl Y025 8RG 




flashing door 


Bug^ War^EM,™ 


£6.96 10 


It the game had been limited to this, rt 


Mulberry Hdubb 
Canning Plaoa 
UvsrpoDi Lt Bja 




■ would have provided a few hours fun and 
would have been as good value as several 
other cassettes reviewed here. However. 


CDS MKro Systems GoMe-s-a 
10 WesiNek) Close 


hos! £5.95 7 


on passing through the door, poor Willy 
enters another cave — the Cold Room, 






wiih different levels and angry penguins 


SVorkshireONIi9LA 




guarding it. Leaping over them Is the only 


Abacus Piograma Sannrel 


£500 B 


way lo achieve success. This cave is by no 


716 LlBhgyfBlach Road 
Swansea SA5 9EL 




each one with different creatures and 


Elfif> Software J3>vir 


E4.96 5 


diflerent Ischniques to solve before they 


BHItery Hoad 




"^^Jhe ^am'et^hosen for the caves are 


No>lolk^R30^NN 




very tongue-in-cheek and will be instantly 
recognised by arcade freaks — Affaclr ol 


ICL'Sinclair emBassy A. 


jau« E4.95 5 


the Mutant Telephones and Wacky 


Slanhope Road 




AwoBbatrons being two examples. My 


Camberlar 




favourite cave is called Eugene's Lair. 


Surrey GUIS 3PS 




clearly aimed al a certain well-known 


Imagine Soltware Schizoids 
Masins Buildings Jun'OmgJs 


k ti.so '0 


programmer This cave is full of malevo- 
lent WC's, complete with Happing seals. 


EichanBe Street Easl 




In addition to the excellent game fonnal. 


Liverpool 










opening tiile with moving piano keys and a 
demons 1 rat ion ol all the caves in the 
system. Accompanying music can be 


Romirt Software Spedra Smash £6.99 6 


272 Argyll Avenue 




turned off at any time. 


Slougri SI ( aHE 




This game is so original, amusing and 


Silversott Mwchgr 


£5.95 


habit-formlng. 11 will probably be voled f>Jo 
1 Speclrum game this year. II 1 ever meet 






Matthew Smith, the author ol this game 1 


L^«nWB 




shall complain most bitterly about the 
program being released during the sum- 


Soltek Ff'BtonM 


£5.95 7 


mer. Were It not for this game, 1 would 


t»13HenriBltaStrael 




ceriainly be more sun-tanned than 1 am at 


London WC2 




present' ■ 



PROGRAMMING 



Single ship combat 



i], 500+ ((iring 'outine] ar 



1600+ 



Peter Bartley presents Alien 
Destroyer in the final part of his 
gameswnting series 

I program ulilising many of Ihe (deas we 
have bean considering ever Itie pasl few 

) object of the game is fo deslroy as 
of Hie alien tleel as possible in single 

supply and need one unit of energy to gel 
back to youi home base. However, your 
laser is solar-BOweied and fienca uses 
none of the ship's energy (ie: you have 
unlimited nring). A five second warning 
sounds before you have lo retire from the 

jr ship's sensors can give you certain 
[nfomiation: a lone sounds and the sights 
align when the enemy ship is within 11 ring 
range. When the ship can be hit, the 
vulnerabie portion Is illuminaled in green. 
Ttie ship turns red when In line of lire, bul 
cannot be hit. When you are close enough 
to the enemy ship, your navigation system 
will take over the aiming for you and 

The controls of your ship are diltitiult to 

colon-'ighl. lull s(op=do*n, K=fire, i 
@-lrac^ (tracking mode: the ship will 
£^W8ys tie moving in the last direction i 

the ship will remain relatively stable). The ■ 
difficulty lies in the fact that the motion ot ■ 
your cratt is relative. For example, if you 






le enemy would 
4 of hitting the key which 



corresponds to the relative pi 
enemy on the screen. 

The first program is a 
simply defines the charat 
using in the game. Run the 
theh New It and Load the se 
(though not before Ssv/ng ti 
ol course). Line 10 reduces 
memory Basic thinks it ha; 



ind program 
le smouhi ot 



character: lor those who missed the sec- 
tion In the fourth article ol the series, here s 
how to oblain it. When typing the line tor 
the first time, leave a space where the H 
should be. Return the line, and move the 
cursor up and onto the space you left. 
Type -{RVS OW/" and then hit H A 
have appeared This 



highsci 
(the "k 

Other lines of importance: 210 checks 
whether there Is a target In the sights. 
Lines 540-590 C 
always prefer It w 
explained so: line 140 has three spaces 
and three [CSR BACKjs in it. Una 640 Is: 

"110 CSH RT] |3 CSR DN| ISHIFTfo ] (SPACEj 

|SHIFrL||CSHDN||3CERLFT]|aSPACES|icSn 

ON||3CSRI.FI||SHIFTP||SPAC6]|SHIFTO| 

Line 670 is: 

■■|IOCSR HT| I3CSH l!N| [SPACEj ISHIR - | 
I SPACE I [CSH [Wi |3 CSfl LFT] | SHIFT •..) [CSn 
m\ [3CSH BKj |SPACE||SH1FT - j iSPACEr 

Note that both lines have jRVS ONj 
commands contained In them. This Is tnje 
ot all the Print statements in the program, 
except tnr^se contained in any of the lir 
400-470 (remember I 









Ohiy our date from the loader program). 



rvlain vari 
arrow and B \'. 









A gives the position ot , 
n of the gulden 
"general-purpose" 



jn get to 



IS working in pairs. Unes 130 



Oh your own "pet" ideas. 
If you do have a playable game, i 

hesitate to send il to Popular Computing 
Weeldy, following the instnjctions given al 
the tyeginning of each Open Forum. Think 



)f progra 



r Vic u 
■US. And If 



f^ogrsml 

10 Pl]KE52.27T0KE5S,27^CLR 

20 FORfl=7168T07231 ^REflDB'POKEfi.B^NEXT 

30 FORfl=7424TO7431'POKEn,0:NEJ^T 

40 lfflTfli6,56,15,16-16,16-56,.16 

56 BflTRSS, 66.. 153.. 231. 155^153,90.60 

50 rflTR2, 4.6.5-5.5.4,2 

70 BflTfiS4.32,S6. 169. 160.96,32-64 

30 DRTfig, 0,66.255. 66, 0.0,0 

?0 TfiTfW, 0,0, 193.34,20,8.0 

100 DRTfl0,. 32,66.255.66,32, 0.0 

110 DflTfl52.65, 131.66,149, 132,105.96 



Program 2 

10 P0KE36879.8:P0V:E36eT9,15;PRINT"naiB'' 
20 POKE36e69,255:I)':0>*-22:Da)=22-D<2>=- 

^D(3)=l Tl*-"800800" 
100 PRINT"T:R=7702+INTi:RHD':1)*484>: 

POKE770 1.230 
1 10 FCH?B=3S643T03e662 ■ POKES, 2 ■ NEXT : 

P0KE3S653,5 
120 POKE7911,0iPOKE7955,0-POKE38421,lNT 

(RND<1)*7)+1 
130 lFVflL<TI*»=^5THENPCKE3G874.200:IFTI 



*>■ " 0901 00" THENOOTO400 
PRINT"aDOEI€RGV- mi"63-VRL(TIt> 
a PRINT"rTflB<llJ"alHITS-"SC 
a P0KER.32:POKER-1.32:P0KEft+l,32 
3 fl=fl+D': IHKRNDO 5#4J )+£ = IFR<7690*22 

THENfl=R+484 
3 IFR>ei64*22THENfl=R-484 
3 P0KEFI..pP0KEfl-1.2:P0KEfl+l,3 
5 F=IKT': (fl-768a).^22)*22+7701 ■ IFfl+lO 

FRNDflOFflNDfi-lOFTHENPOKEF.ePOKEF 

+30720.4 
IF''EEK(7933K>32THEHPOKE36876,240; 

PGKE791 1,4; P0KE7955 . 4 : P0KE36e76. 
5 IFPEEI«7933>=ITHEN600 
P='PEEi«197J 
1FP=13THENE=22 
IFP=45THENE=-l 
lFP=37THENE=-22 
IFP=21THENE=1 
1FP=53THENE=9 
e IFP=44THENGOSUB500:IFX=1THEN;.!=0 

GOTCI100 
9 POKEF.32:POKEF+30720.1 
IFVnL<TI«»=55THENPOKE36874,0 
POKe!98,0:QOTO120 

POPUUHB COMPUTING W 



PROGRAMMING 



"a 



400 P0KE368?4 . 9 : FORE=0TO253 ■ P0KE7933+B, 

170 P0KE39653+B- 5 P0KE7933-B, 173 ■ 

P0f-E3SG5 3-B,5 
410 NEXT POKElSS.e'POKESeseS. 240- PRINT" 

3SOWV0U SCORED' a"SC 
426 IFSC>HSTHENHS=SC-PRINT"iani'OLi HAVE THE 

HIOHSCOPEJBkPLEflSE TVPE VOUR NflflE" ' IN 

pure* 

430 PPINT"«W"C*" HRS THE" 

440 PPINT"KHlf3HSC0RE blITH"HS 

430 PRINT"mWW HIT fl KEV TO RESTART " 

460 GETFf ■IFP$="'*THEH460 

470 SC=0-GOTO20 

5B0 FORB=0TO8 

510 P0KE7923+B.5POKE7942-B,5:P0KE36876. 

24!~E-NEXT 
520 FORB=0TOe : P0KE7923+B. 32 ■■ P0KE7942-B- 32 

■ P0KE36876-241-B- HE>!T ■ P0KE36876. 9 
530 1FPEEK':7533>=32THENPETURN 
540 H*=TI» 
558 FORB»eT09-POKE36877.141-BPOKE7933+B, 

7 ■ P0KE7933-B, 7 ■ P0KE7933-22«B- 7 : 

P0KE7933+22*B,7 ■ 



3 P0KE7933+B . 32 : P0KE7933-B - 32 ■ P0KE7933 

-22«B . 32 ■ P0KE7933+22*B .. 32 : WE!<T 
SC=Si:+50:X=l 
FORB=15TCI0STEP-.1'POKE36877,150-B'> 

POKE3S878,B-NEXT-POKE36877,0: 

P0KE3e878,15 
3 TI*=flS RETURN 
3 B«=TI* 
3 FORB=0TOe : P0KE7923+B. 4 ■ P0KE7943-B. 4 ■ 

P0k;E38643+B, 1 : P0KE38663-B, 1 : POKE 

36B77.22 5+B«2 
P0KE7923+B. 32 : P0Ke7943-B. 32 ■ NEXT : 

POKE7931,4:PCiKE7935.4:POKE36e77.0 
? PRINT^aa rtfCGCKED ON*- 

■' ■PnK:E36876.0-FORB=lTO28-NEXT 
3 IFIHT(0/5)=C;/5THENPRIHT"aa»MIM*M» 

tmsu uaiH mm r" 

a IFPEEf«197>=44THENGOSUB500:SC=SC-20* 

TIt=Bf ;X=0:COTOI00 
PR I NT" a* 

" ■ P0KE3587e, 240 : F0RB=1T029 ; NEJ<T 
3 IFlNT<i3'n0)=O^10THENPRINT" 

MDnN 
0=0+PQ0T063B 





You want to program your own Arcade Games? 

^^^ Sof IwareSTUDIOS 

Gamo 
Dcjlgncr 

Now you can! Produce yourown 

SPRITE BASED MACHINE CODE 

Arcade Games 

NO programming knowledge needed 
EIGHT preprogrammed games include; 




SPECTRUM 



The rings of Saturn 

Maurice Gavin presents the rings of Saturn for 16K Spectrum 



to impress — be n beginner or expert a 
This program does the next best thing 
probably represents tfis most accu 
computer simulation ot Selutn i 



superior 1o many mainframe etforls. wilh 
Ihe Known eiceplion of NASA's Planetary 
Laboratories! 

It features a full screen solid imago, with 
all hidden lines deleted and the globe and 
ring system drawn accurately to scale. The 
user may till the planet and ring system at 
any angle up to 90°. If is Input, the 
planet is drawn as viewed directly over its 
equator with the rings shown edge-on. If 
90° is fnpuf, a polar view is presented wilh 
the ring system completely encircling the 
planet. You may select a northern or 
Bouthem aspect (or the tilt. An Input of s 
will show the underside of Ihe rings ar 
the equator and visible pole correct for th 
aspect. 

The sequence o( drawing the planal 
as follows: 



The program contains an option to Copy 
the completed picture to Ihe ZX printer or 

Screen command. The latter is simplicity 
itself ^ it is only necessary to press "d" 
(lor picture) and start Ihe recorder lo Save 
the picture you have created. The angle of 
tilt is automalicaliy Savedin the hie name, 

enter Load "sal -23.4"Scresn and the 
Spectrum will search and display Ihe 
appropriate image oft of tape. 
Unlike some uninformed computer pre- 



and Ihe oblaieness as presented. 
As seen from Earth, the appearance of 

26.73° (le. Saturn's axial tilt to its ortHt atxmt 
the Sun) in both north or south directions, 
plus or minus 0,49° depending on the 
relative positions of Earth and Saturn in 
their ortjits at the lime. Thus, any flit in 
excess ot 28° will represent a viewpoint 
other than from Earth! 
The Rem slalemanls show the general 



Q of tl 



I prograi 



f, circular (encept for the polar view) and so 
„ the Circle command cannot be used to 
draw the planet. This oval (or correctly 
termed oblate spheroid) shape is due to 
g Saturn's rapid axial rotation in lOh 14m 
ig (Saturn's day), causing the equatonal 



Drawing the globe and rings, it is only 
necessary to calculate the outline of one 
quadrant of the ellipse and to mirror this in 
the remaining three quadrants by Drawing 
each quadrant sequentially. Such a routine 
ensures the Orax^'n^ is executed rapidly, 
with the minimum of calculation to ^ow Ihe 
program down. In the case of the rouline lo 
Draw the Cassini Division in the hng 
system, I have chosen to Plot one com- 

iy slow, though satisfying, this proves to 

Because the whole of Ihe a 



I prog- 






m Draws the glob( 



'flatlening ". The Spec- 

■ ring system via 

using a rapid ellipse 



i of II 



, the 



lb I lily to 
rapidly 1 have included as 
nsutine the short program called Solid 
Ellipse. It can easily be incorporated into 
your program if you wish to Draw these 



BfBriiiM]iaiei>s5sioiiiii from 10 percent to 7ero (full circle) is 
lysiem applied progressively thnDugh the change 

aaooasglobeacMra- q, ,j|, fjom 0' tO 90°. Similarly, the posilion 
nn nno svwom- cioo.- of the equalor and visible pole are correct- 
ly located according to the lilt of the planet 



9 Plot pi 



i both II 






i). The 
place ot y In I 



illipse (called the semi-major 
it precisely how il 




COMPUTING WEEKLY I 



SPECTRUM 



IB 


by Maurice Gavin 


f» 


LET 5C=a. BORDER ». PBPEH a 










SpWSo'^sr.'-TT.tw^i?-.. 












i 


PRINt TRB aa;-ti lt»";z;CMR» 






LET P-COS { {.3*iJ-'ASe«PJJ ; 








































Itf 


PLOT x-i;,M*d 



350 RUN _ 

360 REM Bdratt i 

370 FOR /=0 TO 

390 LET a=INT 

390 LET b=INT 

4-l»0 PLOT x+a^st- 

4-ie PLOT x-a ,y* 

*S0 NexT_r 

0.30 REM Bdraa e 

4.*e FOR T^Pl*-5 

. 1: PLOT OUER 1; 

fff^e. NEXT f^ R 

4-S0 REM ■draw O 

*60 LET ■ - - 



l.i«20 STEP ,033 
SIN fin 
COS f»r«oe) 



1 PI»1.S STEP 



TO fl»^ ^Z^^ 



4-S0 REM Bdelete cro behind glob 



. .*2 STEP ,01 



1 LET b=INT 



THEN LET I 



220 ORRU - . _ , - 

H30 PLOT OUER i;x-t,u-<» 

2*0 DRRW cyS.d^S 

ase DRRU OVER l;®,! 

aee plot ouer i;x + c,M-ti 

ES0 PRRW OUER l;e,l 

290 NEXT t ■ GO SUB *60 

300 REM fceny-COPy^CONT^SCREEN* 

330 PRINT we; "Pf ess a ID COPy,£ 



570 PLOT OUER . 
sea RETURN 



sa INPUT "ti II 

Sb'let c=SIN r(.l*; 

4.0 LET X=S5Sy2: LE^ 
100 FOB f =0 TO PI.'S 
IJB LET a-IMT (SIN J 



PRI^^■ "til 
rr u=i7sya 

■ STEP ,01S 



I>RRU 0, -b>a 
e,y.' t>RRU 2S5, 
0,178: OUER 



AF^aCALYPSE 



,1-1 MK-^LJl_.Ay_Y h-'^t 

y\A\\ AnmaimpllniiiiiurtirBmm, 




Apocalypse 



} I -4Sk , 

^ BBC Model B ^« 



Coming soon: 



22-28 SEPTEMBER 19 



^ 



THE ORIC-1 COMPANION 

by Bob Maunder 

ISBN 907211 03 8 
173 pages. Price £6.95 



A thorough telerence 
guide for those Oric-l 
owners who want to get 
to know and use the 
macnine in deptli, 

SKtion 1. BASIC Summary 
Ssction 2: Keywords Guide 
Sectian 3: Screen display 
SBdion 4: Progiani Organisatlan 



This IS the latest In the Companion series, 
ace aimed by Your Computer as 'tar and 
away the best for serious use "' 




Send your cheque for £6.95 



LINSAC 






BBC & EDUCATION 



Circular logic 

Michael Batty shows how to draw circles and ellipses in the first 
of a three-part series on computer graphics 



le programs becon 
I ellipse filling algorithms 
in most simple graphics. 

taster lectimque is lo t>ll the shape in the 
e way 'you mighl shade il man 



1. II you wish to le 






Cles Trv values 

and ellipses wliich compnse Ihe basic and 300 lo si 

elements ol computer art. The uslsI way each image o 

to draw a drcle Is lo calculate points Program 1 

around lis circumlerence and draw be- ler an where 

Iween them. The X, V co-ordinates of each is t»cause tt' 

point are given by the lormulas have to be ei 

x = R*cosnH]aiidy = R«srN(TH) co-ordinates. It is possible, however, to 

where R is the radius and TH the angle compute these functions only once (or a 

from Ihe horiiontal measured counter- smdl fined angle (DT| and to llien use a 

dockwise. 11 we vary TH regularly from to recursive formula based on trigonometric 

360 degrees (or 2«P) radiaris), we trace addition rules lo generate the sequence of 

out the points which lie on the circumfer- X, ¥ values. This technique is used in 

A circle is really a special form ot ellipse shapes are drawn over three limes as fast 

where the vertical and honjontal axes are as in Program 1 , 

the same lenglh. If we change these We now need lo paint or fill these 

lengths by replacing R in Ihe above formu- shapes and we can make use of the 

las by XX, the 'radius' ot Ihe X axis and triangle fill command PLOTSS of BBC 

YY, the 'radius' of the V axis, we generate Basic, It you insert line 120 MOVE 0,0 a^O 

poinls defining an ellipse. Program 1 en- replace line 150 with PtOTSS.X.Vm Prog- 






lI up a 



Program 3, this technique is used, 
that the fill IS from right to left, as though 
you were left handed, because of the way 
circular angles are measured. 

Also, observe that only Ihe points defin- 
ing the top half of the shape are computed. 
Faster fill routines exist even in Basic, b 
this technique is necessary for later worh 

We now have quite a fast method li 
filling an ellipse and we can already 
generate some interesting computer art. 
Program 4 paints random sized ellipse 
random colours al random positions or 
screen, and the illustration shows * 
can bB achieved. To gel some weird 
wonderful effects, alter the operation of the 
Geo/ statement in line 90 and use MODES 
lo generate 16 colours. 

Next week, we will show how th 
shapes can be rotated to generals m 




POPUlj*n COMPUTWG WeEKLV 



BBC & EDUCATION 



PROGRAM 1 


PROGRAM 2 




Id 


REM Slaw Ellipse Drawing 


10 REM Fast Ellipse Drawing 




20 


MQDEl 


20 MODEl 




30 


VDU29,64a;512i 


30 VDU29,640;512; 




na 


REPEAT 


40 REPEAT 




50 


INPUT"RADIUS OF X AXIS = " , 
XX 


50 INPUT''RADIUS OF X AXIS = " 

XX 
60 INPUT"RADIUS OF Y AXIS = " 




60 


INPUT"RADIUS DP Y AXIS = ", 






YY 


YY 




70 


TIME=0 


70 TIME=0 




B0 


N=6a:DT=2*PI/N 


90 N=60!DT=2»PI/N;A=XX/VY 




90 


MOVE XX,0;TH=0 


90 X-XX:Y=aiMOVE X,Y 




100 


FOR I-/.= I TD N 


100 C-COS(DT)!S=SIN(DT) ; SS=S/fl 




110 


TH=TH+DT 


S=S*A 




130 


X=XX»COS(TH) 


110 FOR r/.= l TD N 




140 


V=VY*SIN(TH) 


130 T=X»C-Y*B 




150 


DRAW X,Y 


140 Y=Y*C+X»SS:X=T 




160 


NEXT IV. 


150 DRAW X,Y 




170 


PRINT"TIME TAKEN = " ; TIME 


160 NEXT 17. 




1B0 


A=GET;CLS 


170 PRINT"TIME TAKEN = "-.TIME 




190 


UNTIL FALSE 


18B A=QET!CL5 




200 


END 


190 UNTIL FALSE 
200 END 








PROGRAM 4 




PROGRAM 3 










10 REM Random Ellipses 




10 


REM Fast Draw, Fast Fill 


20 REM tClMichael Batty, 1903 




20 


MODE! 


30 MDDEl 




30 


VDU29.640;512i 


40 VDU19, 0,4(3; 19,1, S;0; 




40 


REPEAT 


50 VDU19,2,6;a;19,3,7!0j 




50 


INPUT"RADIUS OF X AXIS = ", 


60 VDU5 






XX 


70 DT=PI/30tC=COS{DT) !S=SIN(DT) 




60 


INPUT"RADIUS DP Y AXIS = ", 
YY 


B0 REPEAT 

90 VDU29,RND( 1279) iRND( 1023) ( 




70 


TIME=0 


100 GCOL0,RND(3! 




80 


N=30!DT=PI/N!A='XX/YY 


110 XX=20+RND<150) !YY=20+RND 




90 


C=cns (DT) :S=SIN (DT) ! SS=S/A: 


(150) 






S=S»A 


120 PRaCSHAPE<XX,YY,C,S) 




1B0 


X=XX*C: Y=YY»S 


130 UNTIL FALSE 




110 


MOVE XX,0!MOVE X,Y:PLDT85, 


140 END 






X,-Y 


J50 DEFPRDCBHAPE(XX,YY,C,S) 




120 


FOR I7.=2 TO N-1 


160 A=XX/YY:BX=S/AiSY=S»A 




130 


T=X*C-Y»S 


170 X=XX*C:Y=YY*S 




14B 


Y=Y»C+X»SS:X=T 


IBB MOVE XX,0:MDVE X , Yi PL0T85 , X , 


-Y 


150 


PLOTBS , X , Y : PL0TB5 , X , -Y 


190 FOR IX=2 TO 29 




160 


NEXT IV. 


200 T=X*C-Y»SY 




170 


PLOTS5,-XX,0 


210 Y=Y»C+X»SXlX=T 




1S0 


PRINT"TIME TAKEN = ";T1ME 


220 PLOTSS , X , Y I PL0TB5 , X , -Y 




190 


A=GET!CLS 


230 NEXT I"/. 




200 


UNTIL FALSE 


240 PLQTB5,-XX,0 




210 


END 


250 ENDPROC 





22-28 SEPTEMBER1BB3 



48KSPECTBUM 



The best books for the 

SUNSHINE Drago"^ ^^ 

Q^gon32 The Working Dragon 

n ' 



Dragon 32 Games Mosler 

«lowrilB/OLjrowntople 



News, May 20 1933 

The Dragon Troiner 



recommend Ihe Brains booh c 
of (hfs select/on " Which MJcr 

Advanced Sounds 8 Graphk 
for the Dragon Compuli 

All Ihe Tiajor aspects ol the sou 




r 




The best books for the 

SUNSHINE Micro Adventurer 

Spectrum Adventures r-----''''''7ueu!^f^"'^*ures 

A ^iorworK by Tony Bridge ond \-^ .,0^ ^^^^S^ V° "'"";, 
Hoy Cornell which details the growth \ * invinQ o"** I^ a RoV '^°'" 
and development of Adventure \ ;, gu.de '° fL lonV Bndge^ 



■ning and then pre' 

graphic Adventure 

\ 'The Eye of the Stor 

i ISSN: '516408 07 6 




quMai: 01-734 3454 



Commodore 64 
Adventures 

A blueprint for the cons 
playing of Adventure prograt 
bosed on a full text Advenli. " 
ISBN: 946408 114 



Pleose !ond ma 


aila\ ordar for 
ne Boohs. I3'l 


n 


pa,ablE Id Sun!h 


LiltlaNavponSt., 1 


.J- 1 








W. can no 


mollyd.liv..in4/5doy., ■ 



POPULAR COMPUTIMG W 



COMMODORE 64 



A bit-mapped screen 



The first in a two-part series 
on hl-res graphics 

Thougfi the possibililies provided by 
user-detined characters and sprilss ara 
Blmosl litnilless, the 64 does provide yel 
another major graphrcs mode, bil-mapped 

one of Itie 1 ,000 character squares on the 
normal scrasn, Ifie user is able lo set any 
individual pixel (short lor picture element) 

or dol on the scresn. In Ihis mode line 






The 8K ol memoty necessary to hold ll 
■mapped screen is obviously not stf 

normal 1 K screen memory nc 

I it even use thai ai 






have the necessary in 
Basic. Aa with the Sprites program, I 
POKES should be included In a lose 
program which is run BEFORE the mi 
program. The program as given ht 
■ a happily within the 6K ot memoty up 



2023 li 

store colour information (oi the bit -mapped 
screen. The solution adopted in the prog- 
ram that lollows is to locate the screen 
beginning at 8192, leaving 6K ot memory 
for the Basic program, with the option ot 
relocalrng Basic if the program is de- 
veloped and lengthened. Using the prog- 



B192 — 



isilyei 



niose 



III dictate 



lit -mapped st 






e graphics line-drawing algollhm 



I variety ol lleiibiB 



To understand the prograi 



it- mapped screen is s( 
screen itself contains 320.20 
positions, a total of 64,000. 
store each of these separa 
bytes of memory are needec 



^afnuslbaPOKEdml 



bytes (the 8«B gnd that we used for 

user-defined graphics). Starting from the 

top left-hand corner of Ihe scresn, the firsi 

10-71 bytes of the screen memory i 






1 the 



Tfie second eighl bytes form the second 
B'8 grid and so on along Ihe line. Since 
there are 40 character positions in a line, 
each line lakes 330 bytes. In actual fact, 
■mapped 



Module 3.4.1 

This module configures the 
ory for the bit- mapped r 
some useful functions and i 



individual pixels to 
of 8-8 gi 



e addre: 



Commenlary 

Line 10025: The POKEs in this REM 
Statement are nol necessary for the run- 
ning of this program. They are included in 



Lines 10027-10023: The us 
lunctions IS given in the table of variables. 
Line 10030: 53272 is the register 
used to contreil where the VIC II 
character data, m this case it w 
the beginning of Ihe bil-mapped screet 
POKEing B in hare sets the screen start I 
8192. POKEing 53265 with 32 sets th 
bit -mapped mode. 

Ijnes 10035-10040: In Line 10022, 1h 
user was given the option ol clearing 1h 
screen During the development of Ih 
program, when Ihe program is slopped 
and RUN-RESTORE pressed, alteral' 
can be made to the program without 
allBOIing Ihe contents of the screei 
On running the program again it 
time not lo have lo clear the 8000 byies. 
Line 10050: This line clears t 
screen memory area, which is 
ployed lo hold Ihe colour data tor each of 
the 1000 normal character pos 
Tosling Module 3.4.1 
On lirsl running the program, tl 
should immediately fill with garSage. Gra- 
dually this wilt clear, leaving a screei 
which may still be covered with coloured 
squares corresponding to the position of 
characters on Ihe normal mode s 
These too should then begin to clear and 
the screen be set lo white. \ 
module is linished, press RUN and RES- 
TORE lo return lo normal mode. ~ 
Continued ne<l 



id bar) . program 



t^DBV, 



VBi*'!iaCBlm 



1 0000 REMtt*-*****H(***«**«*********«***** 

10010 REM IHITIRLISE Hl-RES SCREEN 

1 0020 REri*^««*««**«**!«%**************** 

10022 CL«=""; INPUT "HSCLEflR SCREEN <V/N> 

:";CLt 

10025 REM POKE 44,64:P0KE 43..i-P0KE 1638 

4,0:CLR 

10027 UEF FHPPc:x:'=SC+320*INT(;V/S>+?*IHT<; 

X/S^ + CV RHIi ?> 

1002S DEF FMPV':X>=PEEK<FNPP(X>> OR i;2t<7 

-tX AND 7>)) 

10029 DEF FNPEtX>=PEEKi;FNPP<X>> PHD (255 
-2f(.7-(.K AMD 7>?> 

10030 POKE 53272, <PEEK<5327£>>0R STROKE 
53265,. PEEK t:532S5> 0R32.SC=3192 

10035 IF CL*="H" THEN 10050 

10040 FOR I=3C TO SC+7999'POKE 1.0 'NEXT 

10050 FOR 1=1024 TO 2023 : POKE I.6*I6+i2. 

NEXT 

10060 MO?i<0>=2 ■ MOri< U=5 ■ MOK(2:'=10 



23-28 SEPTEWeeH 1983 



SOFTWARE FOR THE DRAOON 


all machine code 




1 lumt ijLMe-!:|l« din. »iri .imjIM 


£i«l:sr: 


E"i=°sS^'''^A?2 






cs™t:.S£f.»sjs."MiS 




rscKJsstsf""™^ 


Sug Ml DnwK nmniiig lol thiMi k. 


i.,rrB.3.ii~*=i*».~i'^ 


SIS^iliwin'M'SllM '"""" ""^^ 








CHBt 


"'^<IW>ltyHSw>I.IU«l>l>l. HlOb* Ml. « Ull CUflSOR «>«l 


























iVMSABil FHau SPECTHiM AnDOWeR OOOD SOFTHMflF D WLEFIS 


J. AAORRISON (micros) 





INTRODUCING 



II you've ever been killed by llie evil goblin, flamed by a 
dragen^or Ijmsd \o slona by a wiianj, then Micro 
^iJusntu'erls the magazine tor you Each issue is packed 



Mnvo ilctvsniurer Aill be launched in Odabei, followed by 
CommoOore Honzons in Nouembar. And you can gel your 
lirsl copy Iree by subsoibing now. For only E10, 13 issues 
of eilliar magazine will be mailed lo you direct — ihs 
nonnal iateis£iO lor s year's subscription 02 issues). 




Subiciiptlon Dapirtment, 1 2r13 Little Newpait Street, 
London WCZR 3LD — along with a cbegue or postal 
order made oayable to Micro Advanturar. TTie special UK 
subscnplion rale is EtO (or 13 issues, overseas it is C16. 



lo Commodore Horizons, 



POPULAR COMPUTING WEEKLY 



DRAGON 

Functioning well . . . -- B 

David Prins presents a numerical analysis technique eso csuh 

for approximating functions ,B5,ln 

This program uses a numerical analysis The dala polnls you enisr will probably 'm-'m ™s & 

iBChnique. known as Ihe Newlon have been oblalned from a sciencsenperi- ^u 

polynomial miBrpolalion melhod, in order menl of simulallon, bul Ihe program can ,009.1010 simple 

10 approsimale a funolion by a polynomial also be used to answer school maths itiskai 

In general, il data is known aDoul a questions regarding straight lines and 

luncllon at Wdifferenl points, then a unique quadratic cunies which pass Ihrough given y^^|g|,|gg 

polynomial exists ot degree (N - 1], which points. ^ ^ 

models Ihe tunclion exactly at the M given It Is important to' note thai approxima- >.,„, f,„,cin) f 

points and appronimalely at other points, lions given by Ihe program are only useful v 

This approKimallon is very good lor func- for "well behaved" polynomial or polyno- t 

linuous, polynomial- like] and woriis best in in the region where the original dala was ^ J 

the neighbourhood of the given data. But, given. Also, you musi not enter any point x.f ^ 

if dala is only known al, for instance, * = 1, more than once in any one set ol data. j 

£, . . . W, you should not rely too much on l □ 1 

Ihe polynomial approximalion at say x = program notes ( 

1000. which is nowhere near the given jj.j.a ^ei up i«!oireO arrays and mpui iiw ^ ' 

points. known rials ' 



^40 


F^R J 


5^0 


D = X( i 


■M,n 


IF 0= 




PCINT 


570 


C1J> = 



REM APPROXIMATION USING INTCfl 300 PHINT-T^ FND CORRECT 1 aNS 1 
POLflTING POLYNOMIALS. TYPE 999»C.O" 

I RE1 ALL POINTS ENTEREO KU?T BE 310 PRI NT :-pril NT "POl NT iiO."; 

OII^FERENT. i?C I'ipiJT l.X.F 

I REM 330 IF 1=991 THFN 510 



TO CLS!PRINT"HH=N PROMPTEO. ENTER . 

POINT AND" 
RO PR1NT-TH6 VALUE OF THE FUNCTION 
90 PR1NT"THE POINT, SEPARATED BY a 

COMMa.":PRINT 
100 PR1NT"F0R EXAMPLE. TO ENT=fi THy 

THE" 
110 pfliNT"FUNCTION HftS THE VALUE 

^.2 AT" 
120 PRINT"TH^ POINT 2.0-' 
130 PWINT-'ENTFR Z .0 .<.. 2" : PR INT 

140 PRINT-IF YOU MAKE A MISTAKE YOl 

CAN" 
150 PRINT'-C^RRECT IT AT THE ENQ." 
160 REM 

170 DIM XtNl.cfNI.CfN) 
laO FOR 1=1 TO N 
190 PP,INT:PRINT"PniNT Ki3.";l: 
2T0 INPUT Xf I I,F1 11 
JIO N=XT I 
2?.0 PRINTiptflNT-OO YOU WANT TO MAKi 



■iO PR1NT"WHFN PRGJ^PTEO. ENTER 

C0HRFCT11N5" 
;60 PRIST'BY TYPING THE h^. Q^ 

?OINT" 
170 PR1NT"YTU WANT TO CORRECT I 
;90 PRINT"C?R''ECTEO VALUE AND 

FUNCTION" 
'90 PRlNT"VALU£t SEPARATED BY ( 



S-2a SEPTEMBER 1983 



670 


GOSUB 


710 






PRINT 


PSIMT 


•DO YOU 




EVALU 


TIOK" 






PRINT 


USING 


THE SA" 




(Y/Nl 


tr.i^Sl. 


1 lODO 


hsr> 


!F AJ 


"Y" T 


4EN 620 


7T1 


CLSIP 


1NT"FNTER TH 




WHICH 


YrU" 




710 


PRI\T 
FuriCT 


ON"! 


TO APP3 


7?n 


INPUT 


K 




7-10 


V=Cll 




=1 THFN 


TAO 




-Z TO 




750 
7An 


V=C(I 
I4EXT 




( 11 1 'V 


770 


PRMT 




XIMATE 


TRO 


PRINT 


■AT"!X 


!"is":v 


7 90 


RCTUR 






I'JO 






1010 IF A 




OR Ai=" 




ELSE 


1000 





OPEN FORUM 



r 



Open Forum Is for you to publish your programs and Ideas. Take care 
that the listings you send In are all bug-tree. Your documentation 
should start with a general description of the program and what It does 
and then give some deialf of how the program Is constructed. We will 
pay the Program otthe Woek double our new lee of E6 for each program 
published. 



-ding tc ■ 



Targat Practise 



on Dragon 
This Is a simple largel stioottng game 

whicfi a cowbo/ fias (o lire al a moving melhod 

large!. The target randomly moves (rom you mill nave lo press ine resei 

top to tiollom and vice-versa. Botti the Oefore using ihemlerlace to either s 

cowboy and the targsl are stored in arrays load programs directly after playing. 



'A' ana B" respectively, since using llie 
command 'PoHe 65A950 to speed up Ihe 
game disables the cassette inleHace. Un- 
less you escape from Ihe program in Ihe 
^hin the program itself 



There a 

age to hit. The updown ar 
cowPoy up and down. The 'shift' 

target pass, as it will reappear s 
no penalty. If your Dragon will n 
the Po/fs leave it out, 
Variables 



AHRAVA Cowboy 



3 REM 
3 REM 
3 REM 
3 REM 
3 REM 
3 REM 
3 REM 

7 CLS 

D PRINXri ed," SHOOTING PRACTICE";PHtNT 

(,i 128,-BYD HASWELL" 
3 SCREENO.I 
Q FORT= 1 TO2000:NEXT 

3 CLS8.PRINT (a 64,' THE UP AND DOWN 
ARROWS MOVE THE 

COWBOY':PRINT:PRINT-TRV TO HIT THE 
MOVING TARGET':PRINT:PRINT"YOU ONLY 
HAVE 1 SHOT PER TARGET" PRINTiPRINT 
"THERE ARE 20 TARGETS TO HIT" 
PRINT:PRINT"YOU NEED NOT HIT THE 
TARGET FIRST TIME!", "THERE IS NO 
PENALTY FOR LETTING IT 
PASS."':PRINT'USE 

■SHIFT" TO FIRE.'" " - - 

8 SCREENO.I 

Q FORT= 1TO80l313:NEXT 

POKE 65495,0 

K = 

DIMA(2Q,3ei 

DIMB(3a,3a) 

PM0DE,1:PCLS 

a DRAWBM3,5:R5D2L7R9L2D6L5NU6L2D10 

R7U10D3L4R10L2U2n4BM2.24; 

R3D12R3L6U12"" 
GET(0,0)-(17,40).A,G 
PCLS 

CIRCLE(10,10),3 
GETIO.O] - (3I3,30),B,G 

4 REM BOTH COWBOY AND TARGET NOW 
STORED 

Q PCLS 

SCREEN1.1 

a FORH = 1T021 

PCLS 

LINE{4,4) - (250,1 86), PSET.B 

5 REM BORDER 

X = 8:Y = RND(50) + 50:P = RNDilOO) + 50 



340 



REM DETERMINE DIRECTIONS OFTARGET 

IFF<0THEL- 190ELSEL = 

S = RND(3) + 3 

S = (SGN(F) . S) 

FORT = LTOABS(L + (- 190)) 

PUT(X,Y) - (X + 17,Y + 40),A,PSET 

IF PEEK(135) = 10 THEN Y = Y +3:PLAY 

■■T15503C" 

IFPEEK(135) = 94THENY = Y-3;PLAY 

"T15503C'" 

IF PEEK(65280) = 1 91 THEN L = 1 :G = Y + 

1 4:PLAY"05T1 55 V30G V25FV20EV1 5D V1 

CVSC" 

IF PEEK(65280) = 255 THEN POKEl 35,0 

IFL = 1 THEN PSET(0,G] 

IFY>144THENY = 144 

IF 0> P - 2 AND O < P + 25 AND G > T AND 

G<T+ 18THENK = K + 1:CIRCLE(P,T),10: 

CIRCLE(P.T1,1 SPLAY 

"T20O1V30GV25FV20evi5DV10 

CV5C" :PCLS:N EXTH :GOTO560 

IFY<6THENY-6 

IFO>250THENO= 17:L = 

0:PLAY"O1T155CCCC"':NEXTH 

PRESET (0,G) 

IFL = 1 THENO = 0+ 15 

PUT (P,T) - (P + 3Q.T + 30),B,PSET 

IF H = 21 THEN 560 

NEXTT 

GOTO320 

PRINT (a 64,'YOU SHOT'K'TARGETS OUT 

OF 20 1'" 

PLAY"'T30V2aCDEFGAB" 

IF K < 10 THEN PRINT'YOU WOULD NEVER 

LIVE IF YOU HAD". "TO DRAW FOR YOUR 

LIFE!" 

IF K > 1 6 THEN PRINT'YOU DRAW 'EM GOOD 

COWBOY!'" 

FORJ=^1TO2000:NEXT 

PRINT (ii 480, "HIT ANY FOR ANOTHER 

GAME.". "OR HIT '£' TO END," 

POKE 135,0 

AS = INKEY$:IF AS = "■"" THEN 620 

iFAS = 'E' THEN POKE 65494,0;END 

RUN 



POPULAR COMPUTING WEEKLY 



OPEN FORUM 



on Vic20 
TiiB Cfogfa"' pfinls a rafiflom maie and 
Ihe player takes the form ot a fliamond al 
■ p of the screen. The odiecl is lo 



impossible to reach (he ball williDUt 
pressing llie B key; when this is pressed 
laze immediately sunounding the 
rd IS demolished. However, using 



Orm 



le computer foimi 



1 rsm********nia2e***** 

2 rem wt-it-teci by a. morris 

3 rem da-te!28/2/S3 

S rem set ■jsriatoles 

9 rein#*#i****#**#i****** 

10 prin-t"a" !s=100000 
20 v=e:m=0 

30 e=int(22*rnd';i)+?7e2> 
40 h=intC22*rndClJ+ei64> 

49 rem print heading 

50 print"*******#«»<3ize»*********" 
£0 firin-t" n;-doiHn i.j;-ur>" 

70 print" h;-le-ft js-right" 

75 print" Si-demolish" 

€0 i»rint"W*«*»««*«*«««**iKi«**««!fi" 
30 +ort»"0to5000inextt;print"a" 

99 rem dr^ maze 

100 poke36879,0 
110 ■fora=lto250 

120 b=intC462*rnd(n+7724> 
130 pokeb,^! 
140 nexta 

150 pol<eh,81 ;3osubll00;geta» 

151 POt<eh,81 jgets* 
160 pokes, 30 

170 i-fai*="n"then«=22[0ioto25e 

180 i-fa*="w"then9i=-22;aoto250 

190 i+a*="h"theng=-l ;9oto250 

200 i-fa*="j"then«)=l!goto25e 

210 i'fat="8-'then«josutol090 

220 gotoISl 

Z50 m=m+l 

251 poke36S78,15:poke3687S,215 

252 ■fort=lto200!ne^<t;poke3687S,0 
260 pokes, 32:e=e+9 

270 i-fpeekte>=91then551 
280 pokee,90 
290 i *e=hthene;00 
300 gotolSl 

551 poke36878,I5:torui=lto6 

552 readn :poke3e875,ri :-forr-=lto200 ; 
next 

553 datal35, 143, 147, 151,153.-163 

556 nextiiu 

557 poke36878, 9 1 restore 

558 poke36879,27 

559 print"a'ou hit a mall!" 

560 input"snother game(y/n) ";g* 
57G i+3*<:>"y"thenprint"SH:hsinks -for 

22-28 SEPTEMBER1983 



completed in so tar. 
Tile piogram incorporates good o 

Program notes 






the gswe" 
580 print"a" 
590 goto20 

600 poke36879,27:print"SEBEreEEBEEl 
well donelyoij mad* it!" 

601 poke36S78,0!Poke36878,15 

602 ■ford=lto20 

S03 hj=int<:rndCl>#50>+175 

604 poke36375,hj ipoke36879,h.j 

605 -fort=ltol00;nextt 

607 nextd , 

608 poke36S7S,0 

603 poke36S79,27!print"SLiteU ctone! 
yoLj m^sde it! " 

619 print"-in "rn" moyes. " 

620 i -f m<sthens=m 

630 print" least mo'.'es= "s 
640 ■fort=ltol000;ne>ct:9oto560 
1000 ifw<3thengotol020 
1010 aotolSI 

1020 pokee+l,32JPokee-l,32 

1021 poke©+22,32ipokee-22,32:v=y+l ; 

1022 poke3S87S,15!Poke36875,255 

1023 tort=lto400!rreMtt 

1024 poke36e7S,0 
1040 return 

1043 rem************** 

1050 rem*play tune**** 

1051 rem*****iMi*W***** 
1100 ■forty=lto27 

III0 poUe36878,15 
1120 re«dc,z 
1130 poke36875,c 
1140 ■fort=Itoz tnextt 
1150 poke36878,0 
1160 nextt^" 
1170 h-estore! return 
use data2I7, 400, 213.-400, 223, 400 
1190 data227, 200, 234,200,230,400 
1200 data227,200,234,2e0,230,400 
1210 data223,400,227,4@0,217,400 
1220 data213,600 
1230 data223,400 

1240 data227,200,234,2e0,230,400 
1250 c(at*227,28e,234,200,230,400 
1260 dat3223^400,227,400,217,400 
1270 data213, 600,227, 400, 217, 400, 
213,600 



OPEN FORUM 



Hankr Pllat 



on Spectrum 
The cockpK ol the aircraft is tilled wiin rows 
of llasfiing ligtits, silently signalling their 
vital messages to you, but your steel blue 
eyes are darting from your Artiliclal Hori- 
zon/Altimeter to your Radarscope as you 
tight tor control ol your E7ni ciatl. Your fuel 
gauge Indicates that you have only 60 
seconds fuel remaining and the cross that 
indicates the ship's position, only 8EI1 
below you, won't Keep steady. 



Only 20tt altitude now, anfl your breath 
Quickens as your Artificial Honzon.'Alti- 
meler shows you to be steady, level and 
slowly dropping. Suddenly your eyes 
widen in disbelief; your Radarscope shows 
that a gust of wind has blown you to one 
side, can you brirvg your Harrier back 
above the small ship betore you crash into 

Program notes 











*** 














fi-S B-i' 


:S JDNES 
































HE5TQHE ~S: 


FDF) c-ai TO a s 


































'■-e7B- 


J ■■ -aee- 


■•,--09a-", ■ 












TS 


3,B: 


DRBU O, 







323 IF fUi=e THEN GO TO SBB 
330 BO SUB 3Sa.- GO TO 120 
34.S LET p=p+.a5 



I LET 
380 PLOT I 



UET I 

UET rd=fd- 



GO TD 180 

_.K,y: DRRU Ot'ER 

l;2ia.2*b; DRRU DUES l;b,-a 

396 PLOT DUER l;j;'-'72,y: DRflU OU 
- - - PLOT DUER l;>i-7a 



PL.crr ouER 1 ; ■ +s , I 



9e PLOT 136jS3: DRRU 118,0: 
OT 193,0: DRRU B . l~a. 
ie0 FOR a=ia to' 12: PRINT RT 

3; ■■ 







rd=a: LET 










LET p-O: GO TO 
































179 


IF aS = '-7'- THEN 


GO TO 370 



OUER i; e.. 



430 LET rij= IN 
K 6: FLR5H 1: CL3 

4dE PLOT B,0: DRRU 2SS,175 
T 255,0: DRRU -25S.175: FOR 

TD BB STEP 10: BEEP .1,20 



PRPER a.- TH 



, 13; ■■_LRNt>ED-- 



CIRC 

_. PRINT RT le 

RT 11,13; -SflFELV.- 

TO aa: BEEP .l.HB; 



ISa GO SUB 3B0 
13a LET 2=INT CRND*1S0) : H* x<3 . 
S THEN LET p =p - . B5 : LET r!(=rd-l 
200 IF 2 JBB THEN LET p=p-i-.a5: L 

ET :-d=.-di-l 

333 LET CU=CU+f3 

230 LET X=103 + 1S* (COS (p*2*PI3 3 

SAB LET i^ = cy+lSCISIN ipi-2*PI}] 

aSB LET 3=IB3-ii: LET b = fy-V 

2Sa LET fU=fU-.17: INK 2: PRINT 
RT 2a-fU,15: INUERSE 1 ; " I" : INU 

ERSE 3: INK 7 

[> »>195 ■ 
3mB IF Ij 

d.2e 



asa PAPER a: ink 7: INUERSE 
CuS : PRINT ■" YOU LRHDED 5RFELY 
": PRINT : PRINT 

RGREED RT f 7a . - 
LET ■ 



:- ^ .-. ^_ TO 51B _ 

a-9B INUERSE 1: CLS : PRINT 

U HRUE CRRSHEO INTO THE SEfi 
EEP 2.5. 

see """ 



GO TO 510 

^.JERSE 1: CL5 : PR^^NT 
HRUE RUN OUT OF FUEL : BEEP 2 



-2 THEN GO T 



510 PRINT 

CORE IS NOU 

ifjT ■■ rhot:he( 



YOUR BEST S 
PRINT : P~ 
: INVERSE 
THEN EO TO 



This program illustrates how Impres 
graphic effects can be achieved with or 
few lines of program. 



OPEN FORUM 



space Egg« 

on BBC Micro 
rhis lype of program has Been a 
jurle a long time The idea is to di 



aliens come out 0l Ihe eggs and daslroy 
you. The eggs fall from the sky. Iirst one at 
a time, and then several al a lime. You 
control a (asl-moving gun base, but you 
will still only gel one shot at each alien 



In entering the [ 
lem will be getting 
exactly right. To 
the program has I 



I i'£iX=0!KB7,=- 




l ENDPRQL 



HMDD255,! 



1 jCHft»250i 



3601F fi»-'>" THEN IF INKEV 
(--1£2)AND B);y.(37BX7.=eXX 
570PRINTTAB(Bl-/.-l,3Ii;SPC<3) 
5aoF'R INTTftB ( BXy.-l , 31 ) J : '/DU22 
590ENDPROC 
6OODEFPROCE1ULLET 
f)10 IF S«<. ."I"' THEN GOT0fi50 
620IF YB7.=0 AI^D NDTINKEVl-ll 
630IF yBV.=0 XB7.=B)tX:SOUNDi:i,l,7,: 

2.20,9 
640 GDTD670 

650IF VB7.=0 AND NOT ADU6L0 OND 
i,60IF ¥E%=0 XBy.=BXV.:SOUt<ID0,l,7,5j3aUNDI, 

2,20,9 
670PRINTTflBO!BX*l,3Ci-VBX)!iVDU127,]l.227 
bSOIF yBy.-2S THEN VBX=0! VDU127, 1 1:ENDPRDC 
i90y8X=¥By.* 1 
700ENDPRDC 
71ODEFPR0COLIEN 
720SDlJND2,-a, (ISC 
73UFUR NIX-"! TO SCX/iO+l 
740IF «B5<>aX-AXy,(Nl/.J) '.3 AND ABS 
-fi¥XlNiy.)'> <2 PRDCSHDT 
- 750IF fl¥XlNiy.l<3 THEN 
760PRINTTftB(AXX<NlV.>-. 

CHR«251iPRlNTTftB(fiXy.(Niy.)-l,A¥; 
770IF RVX(N]X)!30 THEN PROCALMOVt; 

PRQCDEflD 
7BOAY%<NlX)-AVy,(N17.)*l 
7';0NEXT 
BOOENDPROC 
BIODEFPROCSHOT 

B20PRlNTTABlAXX(Niy.J+2,AV"/. (Niy.l-1 
127,127,127,11,9,9,9,127,127,1: 
BJOSCX-SCX* 1 

B50PRINTTABlXEi7.,30-VBy.l i SPi: 1 1 ) : YB: 
XBX— 1 

a&osouND", J, 50, lu 
S70PRiNr TAB (14,0) iscv.; "O" 

aaOENDPRUL 

a90DEFPRLicwAiT (wry.) 



'/2O DEPP ROC DEAD 

93OS0UNDU,-10.7.25 

940FDR C1X=15(J TO 1 STEP - 

r.C17.. !:NEXr 
950 PROCTUNEA 
96bPRlNTTAB(9, 15) "Another 
970«F11 15,1 
9B0fil«=eET» 
990IF- A1»="N" CLSlEND 
1 CiOOCLS 
lOIOGDTO 140 
1020PROCTUNE 



FROCBASE 
'-BX/ 

t,« h THEN IF fiDVALl;4400O AND 
/ 1 BX/=BX/-1 

A«= !■ THEN IF lNKEY<-26)flND BXX; 
'=BX/-1 

A« K THEN IF ADVALK2ZO0 AND 



'. (CDX) 



JiSbii 



1U70NEXT 

10BCiAYy.(lI=-20 

I090ENOPRDC 

1 1 OODEFPRDC I N3 TRUCT 

1 1 lOPRINT ' TAB (14,3! CHR« 1 

1 1 2UPft INI TAB (14,4! CHRI 1 ' 



a-28 SEPTEMBER 1983 



WHAT 



JUMBLY? 



UPGRADE YOUR 
SPECTRUM (^^ 

to 48k J^ 




l/L^LTA RESEARCH UMITEDl 



^«S^ 



nm 



YAHTCEE , - . This traditional dice is for 
one or more players and features superb 

graphiics to enhance your enjoyment 

YAHTCEE is Fascinating, Absorbing and 

Ctiallenging 

SPECIAL OFFER 

Order YAHTCEE today for only 
E7.95 inci, and get a 1 0-game 
cassette FREE 




HIRE 



ZX81/SPECTRUM 
PROGRAM TAPES 



Maks Iha motl ol youf Sinclair ZXai or SpMlrum compull 
by hiring lapet Irom Iha orlolnal loltwara llbraty- NOW I 
OUR SECOND YEAR with ovar 2,000 latlillail mamban 



YOUR FIRST TAPE FREE II you ma thli monrh'i couponl 
"^ " "~ TtieSINCLAIROWNERS' " 

S^ SOFTWARE LIBRARY. .... 

Warren Road, Lias, Hants GU33 7DO, 



POPULAR COMPUTING WEEKLY 



OPEN FORUM 



4iua[JUr-iDi.- 
4-J1J3CUND2,- 



l^aOPRINT" So be wsrneB > " 

i::90PRlNT Press CHRS133! CHR»J36i " ■K.'"i 

i-U0FRINTC;HH«135 CHRS137" for keyboard or 

CHEtiriZ CHRI136i " ■ J" " ; CHRS13S! CHRSl 



I L,ET« If- A«="K" THEN CLSlENDPROC 
nS= .3 THEN CL3:Ei 
LITU 132" 



:pROCTUNEA 



490RESTDRE 157C 
500FDR E=l to 7 
510READE,F ■ 
520READQ,H 
530SDUI>ID1,-15,E,F 
S4asOUND2. -15,G,H 
550NEXT 
StOENDPROC 
70Dfl TA149. 5, 53. S, 129, 5,33,2.137.5, 4 
145,5,49,5,149,5,53,5,157,5,61,5, 
0,53,20 
SSODEFPROCftLMaVE 

59QyDU23, 254,60, 12£., 217, 255, 126, 60,; 
(.OOFF-1 
610FQR CF=1 TQ 30 

^INTTAB(fiXX IN1K1-CF,29)CHRI254; 
630 NEXT 



i+FFl >ZB THEN ENDFfil 



B.OOO FREE TAPES TO 
BE GIVEN AWAY 




il piogiess any In 
i: Tony QritJgB. AdKonljre Ci 
r Compuiing Weekly. 13-13 
n SWeBl, Londor WC2R 3LD. 



ODZ^IP^O 



DRAGON SOFTWARE 



SOFTWARE 







3 




PUDSEY CIVIC CENTRE 



DAWSONS CORNER, STANNINGLEY 

NR LEEDS 

(midway between Leeds and Bradford] 

Admission' AHults 75p. CHHdrBn 50p 



Dragon Dungeon 



Wm 



fTn' 



.T'f'iyi 



DRAGON USERS CLUB 



DRAGON STICKS 




r,- The SINCLAIR OWNERS' 

S'L SOFTWARE LIBRARY.. ™: 

. /T." -A Warren Road, Llss,HanlsGU337DD. 8 






POPULAR COMPUTING WEEKlULV 



Tony Bridge's Adventure Corner 







Dungeon Master 



1 spectrum reviei" 
alraid. Bu\ I have !□ 
IB popular leeling, « 



he mornQhl Is 


nwa 


dAdven 


re programs 


or Ihe good 


old 


Sinclair 




ouiselling otht 


sby 


a factor 












Many ol Ihe 








3 S Ders. This 












souls who once used 


sit around a 




graph paper 


wilh olher like- 




d peopl 


, indulging ir 


Hole-P laying Gam 




E lor short) 



The b 



leoa D 



Dungeons and Dragons 

Created by the venerat)le Gary Gygax 
and Dave Arnsson in Ihe 1 970s, I his gams 
is played, typically, by several people, who 
atiampl to solve Ihe myslenea o( a com- 
' Dungeons (originally, but as ollen 
nowadays. 



" staggeringly disi 
com plan is the brai 
Master, who maps 
players 



n York, 



ht future. 






l.Thls 



d populi 






tkely to 



at of th 






le computar. and These are all lalrly o 



media lor. 

Software companies seem to have been 
very slow in taking up the challenge, 
however, and the only real D S D program 
that I have seen is Dungeon Master, from 
Crystal Computing. Several oiher prog- 
rams, from other companies, lake certain 
aspects ol the D S D njles. and incorporate 
them into programs, bul Dungeon Master 
is a system which the budding Dungeon 
tvl aster can use lo creale his or her own 
Dungeon 

The first program on the tape is the 
eponymous Dungeon Master. Once 
Loaded, the program will ask the player it a 






s system. II not, the Dungeon 
Master will creale one for you. The atlri- 

Sirength, Intelligence. Agility and Charis- 
ma (there are a couple of olhers). Then Ihe 
player ventures into Ihe Dungeon set up by 
Ihe program. In the Dungeon, ihe usual 
Adventure commands, such as Look. 
Keep, Drop, and so on are recognised. 

The Dungeon on this side of the tape is 
merely an e nam pie, however. The 
second side of Crystals tape contains a 
program called Dungeon Creator, which is 
as good as ils word, in allowing the user to 
create a Dungeon ol their own. 

This program is really powerful, and a 
great boon to anyone vaguely intareslefl in 
DSD, Dungeon CreBtor pnivides all Ihe 



exploring ol Ihe caves, encept as a oi vine 
presence, giving Ihe players guarded ih- 
lormation as lo what Ihey can currently 
see. Of how they are fating in bailie. A 
large amount of informalion. rules, and 

until now a whole world of details may be 
when playing RPGs, 
lairly obvious area of explora- 
as computer games are con- 
3 computer, alter alt, would be 



week Tony anOge will be loi 



wnlB lo: Tony BndgB. Adventure (Corner, 
POBUlai Computing Weekly, 12-13 Lllllt 
Newport Street, London tAiC2FI 3LD. 

22-2B SEPTEMBER 1983 



facilill 






__ ._. idify.or 

customised Dungeon for use 
with Dungeon Master. The menu contains. 
Create. Inspect. Extend. Modify. Append. 
Load, Save and Ouii 



Creale 
ol all, 

planned the Dungeon on paper. The prog- 
ram asks how many rooms, or locatior- 
the user requires, and then goes on to s 
up the exits and then conlanis of II 
rooms, all at the user's instigation. A list ol 
fulonsters, in degree of nastiness is pre- 
sented, and the user may stipulate which 

room The same procedure IS adopted with 
weapons and potions. 

Apart from the Monsters and Polions, 
Spells may also be put into ef 
and these range from the Astral Escape 
Spell, through Ihe Rod of Annihila 
the Curse Scroll, each of which h 
different degree of dilficufty. 

Having thus created Ihe Dungeon, the 
user may then Inspect e ' ' 

modify or edit as necessary. Another 
option is to Append, i 
rooms, in a 3D matfix il required. Finally, 
the created Dungeon may be Sai-ed Ic 
tape, and then Loaded into the Dungeon 
Mas/er and explored. 

The system, Injm Crystal Computing, 
will prove to be a welcome friend lo the f 
D enthusiast who may well be making hi 
first loray into the world ot microf 
Dungeon Master.' Creator is Irom the sam 
stable as The Halls ol tlie Things, which 
enthused about a lew weeks ago, an 
although the people behind Crystal Com- 
puting are rather deprecalory of Dungeon 
Master. I very much en)oyed using Ihe 
system. It's probably a bit too complex tc 
be anything other than an amusing way ol 
filling a few spare r 

isily transportable to your own Dungeon. 



vlng difliculties wKh an sdverv 



in touch Mitn ore Papular Computing Weekly 

Ire stumped by a 12-13 Liltte PJewporl Slreel 

aventurer may be Londnn WC2R 3LD 

Dken, you rtiay be Wo shall pubBsh Adventure Hi 

th IhBlr problems each week In their own special Ci 



Adventure Helpline 

Micro 




ZX81, SPECTRUM, DRAGON 
BBC AND VIC 

SOFTWARE LENDING LIBRARY 



E5 for life membership (less than (he cost of a Single 
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membershrp kil including cataiogue, newsletter. 

All tapes lent wilh full manulacturer's permission. 
Send a cheque or postai order for E5 lo Software 
Lending Library, PO Box 3, Caslleford. West Yorks 
stating name, address, and computer type. 



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Commodore 64 onlyE199.95 lOOsol games, books 

Dragon OFtlyE164.95 and accessories 

VIC20 only £133 95 available (or all 

SDBClmm only £98.95 popular Home compulen 

SDectrum4BK only £137 95 including BBC. 

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22-28 SEPTEMBER 1983 



CLASSIFIED 



CALL DIANE DAVIS ON 01-734 2688 FOR SEMI-DISPLAY ADVERTISING 



IGAMES software! 



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LAMANVA SOFTWARE 



DID SOMEONE 

SAY CAPTAIN 

PHOENIX? 



RULE COMPUTERS 



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SPECTRUM PROGRAMS 



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HARDWARE j 



CASSETTE LEADS /^f^m 



CASSETTE LUDS 



VICJO OWKEHSI Ou' Harrpacd eO 

moi'ing OiB RampB* Simoly s« 
PrAvsnts vfBdr 10 CDFTiMJlBT RampBch 
Slalnes & Co , UrLII ?, Roding Tfi 



|h PROM SERVICES 



CLASSIFIED 

ADVERTISING 

RATES: 

Una by Una: For p&taKe indi- 

For companies, Iraders, and ali 
commercisi bodies , 20o oer word, 
mininiuin 20 wotda. 
Satni-dliplay: £5 per single col- 

PWT. Or supply rough soHing 

CondHtaina: All copy (or Classi- 
flad seceon must bo prB-paid. 
ChoQuas and postal ordars should 



Here's my classified ad. 

(Please write your copy In capital letters on the llnea below.) 



.. per word so I owe you £ ... 



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FIOPPIES. casaenss, paps'. Fitaora. 
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OefX MO, MMS, 28 Poglsr Read. 



DRAGON USER 



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RECRUITMENT 



PHOENIX 
SOFTWARE 

Are looking lor Machine- 
Code Arcade-quality 
games. We tiave an idea 
which could make your 
game the best seller m 
Europe. 
Send your program lo 
PHOENIX SOFTWARE 
Spangles House 
116 Marsh Road 
Pinner, Middx. 
or Tel: 

01-866 3353 

NOW!!! 



PHOGRAMHEHS WArfTeD (Baa« 



m^ 



FfOT readers entflsa to bi 



COMPUTER SWAP 



Compalins WceUy. 1 

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1 


1 ick machine code 'rranual, sell lor 
.■..-- Tel, 01-8013019 
!xai 16K, »ilh soldered Ram pack. 
i...™ no proflrara crusher! Complete 

i-.a^ual anO lllm, -. gemes Hooks, t 
■ ■ cassettes, Indudlr-g FligKI S/rmils- 
>.<v, 3DMDnsle^Malza.3DDeler>aei. 
'-',^ Tel;9Se7S56. 
ixat. iSK Ram pach. sound m-piu. 

1 HO 5on»we (15 lapes). leaOs. manu- 
,ii sK very good condil-orr. «onh E250 

ZX81. 16K Ham, iwj manuals, oilers 

0726 20M9 alter 5 pm 

ZXai, 1SK hfenwiBch heyboarfl, AGF 

too Moks, graphlCB Joller, £95 ono 
Tel. 01-301 0432 

KeyWard, incluOes over £60 EoNware. 
BOB., manual, and loads AlioBBinar 

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Wow and rnagaiinsB lor Vic, only 


sen lor £Z00 one Tei Ashiord (Hl» 
dlessK) 55379 

VICMi . C2U. lOysltcK. 32K. £200 ol 
software, both Ram and Rom . maga- 

45021 

Vicag, CZN. £90 ol soHware. joyslia. 

Inlroduotlon 10 Basic manual. Bo.sd as 

ACORN ATOM, tuily e.panoad -t 
gamaf * tioolis and magajmeB. £60 
ono Tel- Noningham aaiOBB 
BBC MODEL A * 32K. Wl oNars 

Includ-ig monl»r^^c«wl»^™™^ 

John, evenings) 

BBC MOOEL B • Iwin Ikjppy drivBB. 

sollware 4. Rom-baseO noflwa™. 

cassBllB gamas, joysllck, books. £140 

rranulMura.; gua.antas + |oy5l«*8. 
556.5182 (aflsr Q pm) 

book, casaellBS. DonKay King. ShuMIs! 
Planel Invaskin. Black Sanclum, De- 
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ATAHI 800 MK BAaC, manuals. 
|oysl«k.C2a5 Tal:D1-5S0 7748 

ATAfll 4011 MK BASIC can-kloe. 

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ATARI VCa. nina rarlndgas. keyboard 

+ BI00lacdrlvB,rranual8 . «.,alick * 
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(07M1M1M0^ °™' ^°' ^"""""^ 
loused ' sollware. only EiOD TbI:!>51 
SPECTRUM 48K. £80 Tel: John on 
SPECTRUM 48K. menuals, ZX Pnn- 

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SPECTRUH MK with bo>es - Fullsr 
(loyboard ( tape recorder ■■ approi 50 

TANDY TRS 80 16K BilandM basic 
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TO SELL OR SWAP. Planal ol DaaDi. 

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sale). 

SWAP YOUR USED SOFTWARE. 

wars. £55. Tel: Watlord 30218 
SPECTRUM GAMES. £3 EACH: Tims 

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SWAP ti»fl volumes of KnBck maga- 

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CB plus Anal plus Mlcroptiona plUB 

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CASSETTES 

10 Cassettes £4.80 

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50 Cassettes £23.30 

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Cheque / P.O. Payable to 




THE wiiincr of t.ur roccnl 
advenlurc cdnipcljlion is f 
Woodward wilh his progr:in. 
The Falls of Shulor. 
Allhraugh a text only iidveti- 
[ure. it was suffii;ienlly im- 
aginalive lo jusi beat off the 

receives a Commodore 64, 

A VicZO was also awarded 
to Mrs K Hildick-Smilh for 

board a space ship orhiling 
an unkniwn planet. 




PROGRAMME DUPLICATION 
Trade enquiries we/come 




— 




■1 B^B ^^ ■ ^^^ LOOK WHAT'S 

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^-\i^^y-> READINGRGI <tSQ- (0734) 591678 Dealer enquW^a wetcomad 



22-28 SEPTEMBER19 



^^WlRt 



[EKcmuH 1 zxei) u-is. 



VNI s cmAQOrtifr.H. 
GEM SOFTWARE 



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We're worth a visJi because: 



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r We've the biggest range o1 Citadel figures for 
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r We've board and adventure games for all ages 
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Games. GDW. Yaquinto. etc, etc. 




NEW RELEASES 



lens for books, publishing 
ises seem also la bo pruduc- 
differenl siiss of book lo 



MACHINE CODE 



Z80 MACHINE 

CODE 

FOR HUMANS 



^^o 



e problem is, uf course, 
particularly lo begin wiih, 
22-28 SEPTEMBER 1983 



people 



gomg 



is given in the form of Oues- 

is -J. loop? What are User 

should make it easier for peo- 
ple [o gel a specific point 
answered wllhout searehing 



Book Baiic Progrni 

prict n.sn 

Mien) Grncial 
PubHsbtr Ncwna Tech 



pteity tough. 

With Z80 Machine Code for 
Humam Granada is Irying to 
simpli^ Ihe task without being 
machine specific. The book is 
designed for the novice — it 



ZHO Machine Cnde !oi 



to get anoiber book — doe.s 
the man ever sleep? 

The latest uddition is Inside 
Your Compuler which Is de- 
signed lo initoduee novices lo ■ 
th<! bits anil pieces 'under the 

Chapters discuss The Basic 
Interpreter, Inputs and Out- 
puts and [he Microprocessor. 

One useful section illus- 



addidt 



:s the CI 









puter (a 48K upgrade 
Spectrum, for example) which 
can be surprisingly difficult. 



NOVICE 

TTte Epson HX-21) tend; 



Gelling Started with I 
Epson HXZO'n. aclually one 
only a few books on t 

intended for the absolv 
novite. The various terms 
Basic are introduced and ilh 

that'theEp^.i'"""' 



The a 



)r Tom Sivi 



specialising in I'ascal an 
this book his intention i 
teach Ihe language througl 
games — perhaps if you h: 
64K Apple and twin 
(which is more or 




The first of wharis likely to be 
a veritable surge of books on 
Adventure games has been 

Tony Bridge, grand inquisi- 



PERSONA]^, 
COMPUTER 



The first section of the book 
examines the history of adven- 
tures and discus.'tes the themes 
common to all of them. Subse- 
quent sections take you 
through the development of 

constructing mazes, creating 

I should add that the 48K 

book was programmed by Roy 
Camell. 



Handbook Is 
a general 



guide t 






enough subjea. it 
some programs a 
lists of computer 

Obviously, it's n 






ch depth — 



EXPENSIVE 

Whatever else American- 
produced computer books are, 
they are expensive — £15.95 
for 214 pages and only black 
and while diagrams is quite a 

Pascal programs for games 
and graphics con.sists of 23 
programs designed for the Ap- 
ple with UCSD Pascal. 



the ir 



more inevitably errors of fact. 
Perhaps the disparate ele- 
ments look a bit cobbled 
together, but it's cheap and 
potential buyers may find it 



NEW RELEASES 




SADISTIC 









a gold m 



Oricmunch appears to offer 
_ll tbe features of the original 
arcade game, includmg Ihe 
priics for good scores like 
cheiries and lemonade. 

Allhough usually you have a 
fighting chance against Ihe 

of them Ihcy double in speed. 
The game is tfre firsi of an 
intended series of arcade 
games to be released by Tan- 
soft over the nest few months. 



only with your trusty .12 and ar 
enigmatic clue "Having ; 
sadistic nature helps". 

The game is said to be high 
ly complex and bO a Savi 



■ BrilliMi Soft' 
IIINenland-: 
Gedling 



A whole range of additu 
Keywords to Spectrum B 
iilahle b) I 






asoft 



The program includes ZA 
new Kev»ord>. and 10 new 
Functions The keywords in 

manipulauon iif Ihe attnbuies 



SNOWMAN 




cimal/hc). 

number fornmlting. 

All Keywords are SimfiiE i^i 
try. with full synlan check ci 
entry. The program, whic 
also provides for a Trace fact 
ity, comes complete with ii 



K Oxford Ri«:d 

Moselcv 

BirminghiiinBI.JVSO 

VICIOUS 

The first part of a "muiii- 

game" is called Usurper and is 
for Ihe 48K Specltum. 






:e(vii 



I against one another until 
one becomes strong enough to 
tackle the King. 

As each player spins out 
their Machiavellian plots, in- 
structing the computer where 
to move, who to kill, fate may 
intercede in the dread form of 
Vampires, ghouls and other 

pTDjfTun ihurpet 

Specfrum JKK 



LILY LIVERED 

!f the gory cover and Ihe warn- 
ing "Parental guidance recom- 
mended for children under 16 
years" are anything to go hy. 
Hells Temple iescuse the pun) 



nouv rii;hes as well as the 
iilotesjid monsters — at each 
stage your computer give.s you 
a 3D vie* of ihe Temples 
catacombs. The producers of 
the game have incorporated a 

club for Hells Temple enlhu- 



GNASHERS 




Richan 
scribed 


Shcpard Software has 
d games which have 
ntlv been in the- lop 


latest program is de- 
as a "30 graphic 
re" and is entitled De- 


vili of 
explore 


ihe Deep. You must 
the lost city of Atlan- 
ale its treasure and 
back to your boat, 
games boasts 1110 
. each depicting a diffe- 
clion of sea bed. The 


brings 
The 


eleclri 


rs of the title are giant 
eels whose one weak 


spot IS their gnashing jaws. 

Around the ocean bed are 
various ohjecis including a 
harpoon gun. harpoons, spade 
and a knife. Sophisticated 



2J-35 Elimholl Une 
I appenham 
Sloufli 

Berks 

fievt RHieases is deaigred K 
let peopla lirow what sa'lwan 
is coming on to IHB mafKet 1 



POPULAR COMPUTING WEEKLY 



Mi.Mii;<ii 




study studies S 

A very similar atiiluds shouW inlluence your 

IVrcfiild". and A' lavels, prompled one parti- chance lo BILdy lewar subjecls in greaier deLail. 

cularly inlarosling rasponse. How you stufly. and whal you BluOy, are 

commenied: "Your saying inal Computer Sci- (I you see educallon merely as a means lo an 

encB A' lavBl Has no real use has only made me end, the end being a |ob. than t Ihirik Ihal is 

more confussd aboularsjnlusmgauQjecl — Iha being short-sighled. The Govemmenl's "Irarn- 

typee OF |Pbs in computing and Ihe puslificaKons mg" inflialives are ol Ihis nature, youngsters — 



■flacifling' slronfl academic (usually non-uocalional| coii- 
ilsubjBCIs. lenl [f you are interesled in languages, lake 



Britain, and 


1 had noi heard ot any ol Ihem 












sically games. We have recantl; 










telephone. 


he opportunities aia changma a 


My 


?vels lined ms perfeclly lor Ihe 


computer ag 


B, even Ihouflh Iha "compuler age 



in- academic. vr>catii 



>mpiiiei scianca degrees. 



Ihey fined so well was Ihe range ol sub|ecls I iry lo e:ilend your Itnowledge by reading widely; 

We all had to lalte Malhemalics. one foreign new things, other than 2ap. 

language, English Language, and English Liler- In compuimg, and relaled areas, you are 

alure. Those tour subjects stiouid be lite basis judged Dy whal you Know and wnal you can do 

olany selection of O' level sulijecls. I Ihenlook ~ not by your qualifications. ■ 

two science subjecle, and two arts supjecls. Boris Allan 



Bght divided 
by four 



Puzile No 74 

"What's eigni diuiOed by lour?" 




woj G H s™»l 


















22-28 SEPTEMBER 1983 



4o Q-c^ ^ © 



ADVERTISEMENT 

' ' SCRIPT FOR TELEVlSI0J|_^ApvERTISEf1ENT 
FOR AUTOMATA. BY^SAmr+ri"^D'^^ 



and sboi^Ajm. Enter camera-left GlWda 
JacJ(Sonj,'Th3Eia^ Tejjblt, ArcWJis^op of 

all laughing. ^ 
toqether. -j 




POPULAR COMPUTING WEEKLY
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